Anecdotal, but quite a few of twitter users I follow, particularly in the OSINT community, have said that they seem to be seeing less “patriotic American right wing” trolls (paraphrasing) in their mentions, etc, since the Russian twitter ban.

Admittedly, you would expect Russia to not block it’s own bot farms, but perhaps if the purpose of the trolls on twitter is primarily disinformation for internal consumption then maybe there is less need of them.