For those who are unaware, lemmy and kbin to a lesser extent are in the early stages of a rapid growth in users, similar to the one Mastodon experienced in November last year.
In a move similar to Twitter, Reddit has all but confirmed that 3rd party apps will be locked out with their new API pricing, effectively forcing people to use the official app or nothing.
That has driven a lot of people to look for alternatives. I expect the wave in new users will ebb, but it will surge back again even larger once the 3rd party reddit apps are officially unusable.