Putin actually getting to Hungary to meet with Trump is more problematic than you might think.
Yes, Hungary itself is a NATO country, but with Orban in control it's an illiberal/managed democracy at best that often bucks the rest of NATO's wishes. So not a huge surprise.
A bigger problem actually is literally how to get Putin to Hungary.
To wit:
Hungary doesn't border Russia, nor does it border any seaport that would allow for easy in and out access.
In theory, the easiest way to get there--as the crow flies--would have Putin flying from Moscow over portions of Belarus (a Russian ally) and Ukraine (the country Russia is currently attempting to overtake).
Obviously, Ukraine is not going to want Putin's plane flying directly over its territory. And my guess is that Putin is too paranoid--perhaps for good reason--to fly over Ukrainian territory at risk of him being, well, Prigozhined.
An alternative would be him flying over Belarus and then cutting through Poland and Slovakia. But both of those countries are NATO and not a fan of Putin at all. Especially Poland. So they might tell Putin to go fuck off as well and deny him airspace.
As such, the only other alternative for Putin is being forced to almost laughably forced to make a huge detour, curve all the way around the Middle East and then over the Mediterranean, up the Adriatic and then over non-NATO Bosnia and Serbia before getting to Hungary.
Now it is possible that Turkey--a NATO country but one like Hungary run by an authoritarian who has at times made some friendly overtures towards Russia--could grant use of its airspace and cut down Putin's detour a bit. But even so, Putin would still have to fly way out of his way to get to a place he would otherwise be able to get to easily.
Sure, I guess Poland and Slovakia could cut Putin a break and grant him airspace. But after all the headaches Putin has caused for them, why should they?