I live in a high-rise in FL and we had 2 tennis courts; one has been turned into a pickleball court and the other is for tennis. My better half and I play tennis and we are in the minority. Pickleball court is busy with play (particularly in the mornings) and they are hosting an all day event this Saturday with food, tournaments and professional instruction as a way of introducing to those that haven't joined in on the fun yet.
I will say this. Those that are playing are both older (55 and above) and in pretty damn good shape. I've asked some of my neighbors if they converted from tennis and all, without an exception, said they have done so. My follow up question regarding if they still play tennis is met with a solid "no" from most, and from those who say they still play tennis, say that their participation in tennis has dropped off dramatically.
It's played outdoors, easier on the joints, can get a good workout in an hour, played in pairs......sounds like a winning combination for most......