I doubt this is the cause. Certain hobbies just grow and shrink. You could get plenty of social media photos photos of lawn bowls for example, but that’s still an aging audience.
Badminton is a bit too far from tennis for my liking (as is ping pong), so I never got into it.
As for the others, padel is far far far more athletic than pickleball (and paddle tennis for that matter), and I would argue even more so than tennis. I grew up playing tennis and I love it, but padel is more finesse and also scratched that itch of learning a whole new sport. I learned it in the UK 3-5 years ago, and I do very much miss it. Literally I think there is one court in all of New England, it is crazy how much of a not-thing it is considering it was invented in Mexico.
What confuses me is there are more old people than there used to be. So in theory "older people stuff" should be thriving. But lots of hobbies / activities / associations are percieved as dying off as elderly members are not replaced. I wonder why.
It's almost like there's another dynamic where each generation is resistant to the pastimes of the previous one, as they make the participants feel old, so they feel the need to invent new ones.
It would be interesting to compare Florida residents with those elsewhere on the east coast to see if they are actually preserving more of these things than we think.
It’s more generational than age specific. It’s not like you turn 70 and now have a burning desire to play croquet. I have no interest in cars but retired boomers can seem to talk about nothing else.