He shouldn’t be allowed to use his NATO membership as a lever to coerce other member states into doing things they are not comfortable with. If Erdogan wants to carry on this track then NATO should be re-evaluating if they want Turkey as a member.
Though I agree with you in spirit on the topic of “a single NATO country that has slipped into autocracy shouldn’t be able to hamstring the whole damn alliance”, in practice, due to the Montreux Convention, Turkey fully controls access to the Black Sea, which was pretty much the entire reason they were invited into NATO in the first place way back in 1952.
Hungary, however, is a different matter, and does not bring significant strategic value to the alliance.
That said, I do think it might be a good idea to make some sort of “override the asshole” provision within NATO, such that a single country couldn’t effectively hold up and materially threaten (through inaction) the security of the entire alliance.
Russia is also not the Threat it was. It still has vast nuclear weaponry. You could argue that having a nuclear threat based in the black sea could prove useful, but would you really want your best technological advantage in such a precarious position. It would take very little to blockade and trap a sub in the black sea. We also have a credible land link to the black sea now.
So yes, this would be true back in the 50’s when Turkey was invited. It is not so much the case now. Military transport is vastly more refined. Even the political landscape around Russia has turned on its head. Turkey’s significance is diminished many fold because of this.
Turkey has been shooting for that for years. The effort stalled after Erdogan and his party got increasingly authoritarian, which the rest of the EU (barring Hungary I guess) really did not like. This was him (hilariously) trying to tie Sweden’s NATO accession to Turkey’s own EU accession, which - besides being absolute nonsense because they’re two entirely separate, albeit largely overlapping geopolitical entities - forced him to do an about-face on that statement roughly 8 hours later.