Seeing a lot of new names in gyms - anyone else?

I've seen more lower level trainers, and less turn-over of somewhat well defended gyms. For example, for a couple of the gyms I frequent, I used to expect my snorlax would stay for an hour or two at most. Now, they have been staying put for a couple days, at least. Maybe, a bunch of higher level trainers lost interest, or Niantech banned a bunch of spoofers.

in my place lvl 29 below doesnt exist anymore, even me just catching mon and evolving without lucky egg on i reach lvl 32 in 4 months due to pokemon spawns rarely

Yes. I think it's a matter of the more casual players catching up to the fanatics.

My area used to be pretty Mystic dominated, but now I'm seeing high level Valor gyms everywhere, every day. I guess that counts as new names?

"It could be 'new phone for Christmas' but I'd have thought getting to lv24 so quickly would be a bit of a stretch."

Could be bots. Could be players with banned accounts starting over.

But also realize that spawns are dramatically increased now compared with the first couple months of the game. My friend decided to let his two young kids start playing a week ago, to eventually use them to bolster his gyms, and they reached level 10 in just a few days without heavy playing.

Niantic banned a lot of players who were spoofing around a couple of weeks ago. A friend of mine at work lost his account so this isn't just a rumor.

This could have two effects (1) making it a little easier for lower level players to get into gyms in some areas and (2) forcing those players to start new accounts. I guess if those players started over, they might now already be at level 15-25, depending on how hard they are playing (or spoofing on new accounts), so this could be some of what you are seeing. I assume their old names wouldn't be available, hence the new names.

We just got companies... Same in our area...

Christmas, being over a month ago is a while back already and level 15 - 24 isn't that high level.

I played daily probably more than casuals and hit Lvl 24 in a little over a month.

I'm sure some people play legit and can easily do that in well less than a month so they are probably legit players.