The rationale they gave is that hate speech appears on these apps, because some of the microblogging sites that can be accessed via Fediverse have this kind of content. Based on this rationale, I look forward to Google Play removing Chrome, Firefox, and all other web browsers from the store as well.
> The rationale they gave is that hate speech appears on these apps,
So does in countless app on the store, and not in the third party content, but app themselves pretty much, and Google don't touch it.
A much more rational assumption is that Google sees the Fediverse as something that can come to steal their cattle (eyeballs,) and they have a plan to subplant it.
You will very soon see them turning even more picky, and eventually remove even censored fediverse apps.
They are repeating the trick they did with uBlock. First, they say do a purge, with an option for the most resistant to "play along," and a few month later, they pull the rug again. This way, they evade an immediate backlash.