I was raised pretty much alone and spent far far too much time on the computer, always online and on the internet other than going to school and "surviving" - was exposed to 4chan at a young age, nobody monitoring what I was doing online, nobody caring for my struggles in school growing up other than "oh you've got great marks, you must be doing well in school!". My parents didn't really pay attention to me growing up other than to serve their own emotional interests which didn't help.
I'm 100% sure it's the primary reason that I'm so socially disadvantaged now in my late 20's - and honestly, probably why my late-diagnosis ADHD and its symptoms are as bad as they are now. The depression and anxieties are huge - and I still spend _far, far_ too much time online recreationally playing video games instead of doing actual work advancing my career.
Yes, the world is increasingly digital - yes, the world is going to be/already is "a computer in every pocket, a device in every room"... that doesn't mean we can't teach our children moderation. Make sure you know what your kids are watching online. Don't substitute parenting with a tablet because you're tired, you had a bad day at work, etc. etc. - I understand there's a lot of specific instances (single mothers/fathers, both parents working long hours, etc. etc.) that encourage this too and it's sad that society has encouraged these behaviors for so long.
A family member of mine allowed her 10 year old to make a TikTok account even though there's a strict age limit of 13 - I shudder to think about the content that the app is filling their easily impressionable mind with at such a young age...
YouTube is a video-sharing service designed to serve as many ads as possible into your eyeballs. It's obvious that if you leave a child to their own devices (hahaha) that they're going to get the full, "un-moderated" Youtube Kids experience. Toy ads disguised as videos, commercial lifestyles disguised as "influencers", etc. etc. I'm sure there's a lot of decent content there but it's up to the parent to teach kids moderation, teach kids to get off the screen and get outside, talk to friends in person, etc. etc.
There's only so much you can do though with the hours you have in a day. Hopefully society changes and begins to realize that these tools are harmful as much as they are helpful if not used properly.