That is a perception.
An alterative explanation is that they are casting a wide net on hate speech, and catching some of the wrong fish.
Perhaps engaging with the hate speech posters is enough to get accidentally caught, the computer algorithm is suboptimal etc,
If this is reported to Elon and he condones the banning of these posters, or declines to take no action, that is definite evidence.
Buying Twitter to silence a few people most of us have never heard of seems unlikely to me,
Banning people on Twitter doesn't stop them speaking up or speaking out elsewhere.
IMO it is unlikely that Elon is publicly encouraging people to engage in debate and then secretly banning them so they can't.
Employees deciding who to ban, and making incorrect or ideological decisions is possible,
I very much doubt Elon himself is personally banning anyone, I also doubt he knows who is being banned on any given day.
He should have more important issues to work on.
Calling for civil debate is optimistic, that is the problem, it will is unlikely to be civil.