Are we likely to see another large-scare exodus to the Threadiverse as reddit begins rolling out age-verification worldwide?

Only if the affected users know about the existence of lemmy, and many of them likely do not. If you happen to still be using reddit, you should use it to shill lemmy, hopefully in a diversity of subreddits so that lemmy doesn’t become any more of an echo chamber than it already is.

Problem here is it relies on people using redit after having found lemmy. I know some people do, but I can only imagine it’s a one-way valve for most.