Earlier quoted context omitted.
Yeah, not really how that works.
Please explain. Having a strong political opinion as an editor and firing your most popular author who has the contrary opinion sounds exactly like what that is. That's just how it appears anyway.
Firing your star columnist by email citing budget concerns doesn't fit the MO.
De-platforming is also not usually deployed in service of mere political disagreement (staunch conservatives speak at institutions that perform no-platforms all the time). It's reserved for positions that are perceived to be outside the bounds of what should be accepted by society such as white supremacy, blatant homophobia, etc.
As far as I'm aware, Dvorak didn't publicly hold any such positions. So even if (and that's a HUGE what-if given the facts) he were let go for ideological concerns, it wouldn't count as a no-platforming move.