Nah I definitely noticed the same thing, it seems to be with new accounts not old accounts.
I think the biggest thing is it seems to be harder to slip past the SMS verification when making accounts. Not only is it coming up more but when I do slip past it my accounts get suspended pretty quick and ask for the SMS verification.
So I think they put a new system in place that makes it easier to trigger SMS verification on unverified accounts.
It could also be just the stuff I was uploading, I made another account recently and uploaded to a totally different niche and the account is still fine, but that could also be because the videos weren't getting flagged as easily so the accounts staying out of trouble.