Lancet is so powerful in this war that I'd be shocked if we aren't currently working on our own version as fast as we can.
CAS is critical to advances. It is somewhat stopped by MANPADS, but stopped very hard by SAMs. When flying close to the trees, physics make it so that a SAM radar can't detect a plane until they are within 5-8 miles. This means intercepting a plane or helicopter attacking the front lines (launching missiles from a distance) puts the radar very close to the front.
Lancet has a range of about 30 miles, so if you place your SAMs close enough to intercept the planes, they are now in striking distance of the Lancet. Because the Lancet flies in so low and has such a tiny radar cross-section, intercepting it is incredibly hard. Even if it is intercepted, using a $4,000,000 missile to destroy a $35,000 drone is a terrible deal. This deal is even worse when you consider Ukraine can't get any more S-300 rockets and Patriot missiles are of very limited production per year (500 or so IIRC).
Going further, our newest 155mm artillery is the M777 and we've given a bunch to Ukraine. Setting aside the maintenance issue (we admitted 30% are in the shop at any given time which isn't surprising given the reliability issues our marines have had with them), their maximum range is under 20 miles which puts them in the range of a Lancet too.
Russia has had to rely on Kornet ATGMs for most of the war. These are direct fire, so hitting the weak top of a tank is almost impossible. There are videos of a Leopard seeming to take a couple Kornet hits and still being serviceable. In contrast, the Lancet offers Russia the ability to do downward attacks at the thin top armor. We have videos of them doing exactly this to take out a Leopard or two. This issue exists not just for tanks, but for artillery and other vehicles based on the Leopard chassis.
Circling back around, this leads to the artillery attrition. Russia has been consistently shooting 5-10x as many shells as Ukraine. Ukraine is basically out of Soviet 152mm shells and doesn't have a great way to replace parts on their Soviet artillery anyway. NATO has basically given all the spare 155mm shells we have. We're ramping up production, but we won't be matching Russia's advantage for a couple more years at the earliest. This is one of the reasons Biden wants to send cluster munitions -- we're out of everything else.
The Russian drone swarms stuff is just propaganda. There's been no evidence of anything like that. The closest to this is definitely Ukraine with all the small suicide drones they've been pushing out which don't work well against armored targets, but work very well against personnel (and you can't hold ground without people).
Western weapons is more about perception than anything. We in America have a superiority complex when it comes to our equipment. When you aren't facing people with AKs and outdated RPGs, our equipment is a lot more vulnerable than people want to believe. Tanks, IFVs, MRAPs, artillery, etc have all been only a little better than Russia's stuff because ATGMs, drones, and mines are proving to be so powerful. On the flip side, Patriot, MANPADS, and Javelin ATGMs have been and continue to be absolutely stellar.
Based on the crushed Ukrainian offensive (still haven't reached the first true defensive line), I can say without reservation that what Ukraine needs is: attack helicopters to work on defense, more ATGMs, 10x as many man-portable EW systems, and an attack drone that actually works.