You just stop using those websites.
Discussion
Idealism is a nice goal, but some people live in the real world and need to use these sites. I've found approaching things pragmatically usually leads to better results in my personal life. YMMV
Ideally enough boomers won't know how to get back into their accounts that they'll kick up a stink about it.
That's the only way I see it being delayed or overturned
I hope the kids prove that these measures are futile and they eventually disappear. Telling teenagers that they can't do something rarely works, and usually backfires in the opposite direction.