Hell. No.
I've been using a gym for most of my adult life. Gyms are anti-social spaces. Big box gyms, sports clubs, the gym at the Y, campus gyms, the gyms that most people go to.
Maybe boutique gyms and gyms where you always work with a personal trainer are different. Every gym I've been to: hell, no.
I'm talking about a full-on gym, with all that, various sport courts (racquetball, squash, etc), a locker room with a sauna, steam room, hot tub, etc., and social spaces with a cafe and seating.
The former expects you to show up, work out, and get out. The latter is a lot more conducive to loitering.
The best way to meet new people and make new friends, in my experience, isn't to simply be somewhere at a regular time - it's to do something which naturally involves interacting with the other participants. In other words, get a hobby.
To give an example: in the last few years I've met and befriended a lot of new people in my area through training in BJJ.
Doesn't everyone do that?
The only way I made friends at gyms was playing a sport - racquetball in my case, took years.
But again - I barely hung out with anyone outside the gym.