The TikTok spying is probably irrelevant since most TikTok users are teenagers.
I was surprised when Putin went ahead and actually invaded Ukraine since I didn't see the cost/benefit justifying the invasion. Putin had a war chest of more than 600 billion dollars. Like half of that was on western banks and it's now frozen, so Putin can't use it. They're burning through the rest quickly as Russian economy is going to the toilet and sanctions are hitting hard. Russia started the war with an inflation of 10% and then it went to 15-17%. Basically all western corporations left Russia. Russian planes are banned to land on most western airports. Russia no longer has access to western technology and global supply chain, which means they can no longer manufacture many things, like cars etc. They're salvaging chips from microwaves and fridges, that desperate they are. Of course China can benefit from it by selling technology to Russia at exorbitant prices, and also by buying Gas and Oil cheaply, but since there's no infrastructure to sell Gas and Oil to China as there is for Europe (like NordStream), that means it takes a very long time for that Gas and Oil to reach China (like 30 days instead of 3 days). Now, Russian economy seems to be doing better than expected, the Ruble stronger than expected, but it's all for the show, in reality they can't hold that position indefinitely. Also if Russia starts opening fronts with other countries they will need to spread their army thin instead of focusing their efforts in one spot. In the months of war so far we've seen how Russian army has low morale and has been ineffective, with seemingly old weapons and tanks, and the territorial gains they won had an expensive cost in lives of russian soldiers and equipment. Theoretically Russia has air force superiority compared to Ukraine but they don't seem to use the full force of their air force. Russia also has a navy and submarines, but that is not very relevant on a land conflict like Ukraine. I thought that maybe they're using conscripted soldiers in Ukraine (cannon fodder) instead of their professional soldiers, to appear weaker, and save their pros for later if the conflict escalates with other countries... that is a possibility.
I think for now Putin will content himself with taking the Donbas and a corridor connecting with Crimea and getting access to the Black Sea, and would be very happy if they could connect that to Odesa and the Transnitria region in Moldova.
Now, Europe will suffer, with inflation now at an average of 10% and many countries relying on russian gas and oil, prices will go even higher and there might be energy shortages in winter (remember, winter is coming). But NATO is avoiding a direct conflict with Russia because that would put two nuclear superpowers on a face to face conflict. USA and Europe are providing hi-tech weapons to Ukraine instead, which has proved to be extremely effective. USA will suffer with inflation/stagflation but not as much as Europe.
Russia has some supporters. Belarus is like a puppet state, it allowed russian forces to use their territory to launch the invasion. Cuba, Nicaragua, Venezuela, and Kyrgyzstan also support Russia. Other middle east countries have expressed their support for Russia, most likely because they don't like USA. Now, would any of these states get actively involved in a war to support Russia? I believe most would not, they're just cheering on the sides. India is also buying Oil and Gas from Russia, and helping Russia with their banking system to bypass sanctions, but I don't think they would get involved in a war against USA and Europe.
China is a special case. Before the Olympics Putin and Xi Jinping met, and allegedly they signed an extended collaboration treaty. China has been repeating russian propaganda and lies (that Ukraine was infested by Nazis and Russia is liberating it etc) and blocking western news about the conflict. China has also bought a lot of oil and gas from Russia. But they are playing a slow game and will play to their own interests. It's good for China that USA and Europe get weakened by the conflict, and it's good for China that Russia is depleting their money resources and get weaker every day.
China has been building a lot of infrastructure in Africa in what some people called Debt Trap Diplomacy. Providing a loan of millions of dollars to a poor African country to build infrastructure, and when they default on their loan, China takes control of the land, effectively having a military base. It is debatable if that is an ongoing strategy or if it just happened in some cases, but China has a lot of interests in Africa, which means they have probably bribed a lot of politicians which they could use in the future if needed. I still haven't figured out what role is this going to play on China Master Plan, but I'm sure there's something there.
Now, will China invade Taiwan? Well, they made a law a few years ago saying that it would be illegal for China not to use any means including violence, to "protect their territory and sovereignity" and recover control of Taiwan. They're violating Taiwan air space daily, they've done so hundreds of times, I suppose to create an opportunity of approaching to Taiwan with the guise of one of these flights when an invasion starts.
In isolation it seems simple, Taiwan army is no match to China army, but it's not so simple. Taiwan produces almost 70% of semiconductors, with TMSC producing most of it. All those fancy M1 and M2 from Apple with 5nm process? They rely on TMSC technology. It is said that in the event of a chinese invasion, Taiwan would destroy their semiconductor fabs. That would have a huge impact on the global economy and affect a lot of products, from computers and phones to cars, fridges, dishwashers... and also weapons. Biden said that the US would defend Taiwan against China at least twice, but his advisors made him backpedal that. Which probably means that it would but he can't say it out loud.
Now, China economy depends a lot on exports to western countries and western economies also depend a lot on products and parts from China. If China invaded Taiwan, it would become an international pariah just like Russia, which would cripple its economy, but it would also collapse the economies of many western countries. That doesn't mean China won't do it, just like Russia did against all odds, and there's a law saying it would be illegal for China not to take any necessary steps to take back control of Taiwan, after all.
About the comment about the US invading Iraq, Afghanistan, Vietnam and Korea etc it's not that if a country invades any country that would become a world war... but Ukraine is different because it's in Europe and if they had let Putin take Ukraine without providing weapons and assistance, from Ukraine it could have tried to take other countries, like Poland, Moldova, some scandinavian countries... USA and Europe can't allow that. And also they can't allow China to take Taiwan for the reasons I mentioned about TMSC and the semiconductor industry.
So, it's not a simple answer... There will be a WWIII, most likely no, but it's not completely off the table.