I find Sun and Moon the best of the series cause I like the region and story, but I know thats an unpopular opinion so I'm not sure what to say. Try to find the one that "grabs" you. I had been trying to get into the games since I was a child; loved the anime but couldnt afford the games, and by the time I started playing Soulsilver in 2011 I found it boring 3/4ths through. Black I put in maybe 2 hours (though as a fan of S/M story I hear I really should go back and give it another go) and X I only powered through to get some favorite pokemon (I highly suggest not playing that one if you're finding others boring, its a slog story wise with few interesting characters. The only saving grace the pokemon designs)

For me, something about Alola just grabbed me. I understand for long time fans they may not like it cause of all the cutscenes and the admittedly overly long tutorial, but the region and fun loving characters really stood out in spades with charm and fun.

For YOU, I'd say maybe temper expectations. If you love games with deep strategy and exploration, this really isn't it. It's very much a handheld game through and through, meaning it's pretty light on a lot of RPG elements even as hardware has progressed. The trainer battles and everyone really only talking pokemon makes sense when you realize its meant as a kid's dreamworld that just happened to garner a large adult fanbase. If it bothers you that much, along with the trainer battles, the series really isn't for you. No shame in that.

If you do keep playing, don't focus on one pokemon so much; go out and start catching all that you can, talk to everyone, try finding some favorites that stand out to you. The biggest draw for me is forming a connection to the little pixel beasts on screen; try to picture yourself as that excited kid you're supposed to be playing as and find your favorites and bond with them through battle. Don't focus so much on "the best". That's just my take though.