If you can't compete on features you've got to compete by making it harder for the opposition. Adding something to support a new regulation is trivial for them. But a dozen slightly different rules in different parts of the world make it really really hard to bring up a new Facebook competitor.
With the amount of regulations and paperwork from osa (which I've long said was designed to prevent an English Facebook competitor) it would be a wild amount of work for a new social media company that wants to be focusing on features but now need to get a legal team too.
The other advantage to Facebook of age verification is that they don't need tracking cookies and other hacks to know what you're doing online. They'll have your fucking driving license, passport, or gov ID. For them it's a massive bonus


