Star Trek directed by someone who doesn't like Star Trek. There were a lot of people on those movies who really loved Star Trek and it showed through. They're not the best, that's for sure, but I still like them for what they are. However I will say that Beyond is definitely my favorite. Might have something to do with JJ not directing it at all and it feeling like an interesting mix of a TOS episode and Kelvin timeline action/adventure.
I think Beyond was my least favorite of the newer ones personally, but I'd still put it above the last time I watched Motion Picture so it seems silly to me to trash those while elevating all the old ones.
Star Trek is a universe of things between campy and serious. It's possible enjoy them all, or ignore the ones to don't.
No one really does that though. The Motion Picture being a bad a movie is widely acknowledged by pretty much everyone. The classics are II-VI, except for V which also sucks.
III is ok but I wouldn't say it's bad. At least not as bad as TMP and V. There's always people being contrarians about movies though. The general consensus is that TMP is super boring.
Of course everyone has their own taste. Maybe some people like how slow TMP is. It's a very different movie from the Abrams series so I wouldn't automatically invalidate someone who liked it but not the new ones. I can't stand Abrams' hectic/ADHD filming style so I've never liked his take on ST. But that doesn't mean the old ones are all good, the TNG movies are basically all trash except for first contact.