Windsurfing came and went in the 80’s - it was the cool thing n then it wasn’t.
I am a windsurfer myself, but i don't think you can compare the pickleball hype to the windsurfing hype, let me try to explain...
I learned the basics of windsurfing (basically boardsailing at that time) as a kid, because we lived at walking distance from a lake. We then moved to the city, so i stopped windsurfing. Then my 2 years older brother turned 18 (got his driving license) and thought it might be fun to pick up windsurfing again. So we went out and purchased a (lot smaller then what i learned it on) windsurfing kit. It was significantly more difficult than on the larger kit, leading to my brother giving up on learning how to do it after a short while. I was more persistent and kept on trying and improving. Then after "getting on the plane" for the first time, you are basically hooked, so i kept on learning and improving. Got my own car and newer (smaller/lighter/more expensive) windsurfing gear until i had 3 boards and 5 sails to surf in almost all conditions above 10knots windspeed. It was a 45 minute drive for me to the nearest water and i was a student at that time, so whenever there was wind predicted, my colleges would magically be cancelled and i would have time to go surfing. But even then, there were countless days where the predictions fell short and i was spending the day waiting for wind (while having fun with my fellow addicts that came to the shore). Then i started working and got into tennis and did not have time to spend at least half a day to go surfing. I (and most of my windsurfing friends) started windsurfing again when there was a bit more free time, but still it takes a lot of planning to go and a lot of luck for the conditions to be good.
Which leads to the comparison with pickleball.....I think it is better to compare pickleball to kitesurfing (and wing (foil)surfing maybe). Kitesurfing took off big time and surpassed windsurfing for a number of reasons. It is a lot easier to learn (you can be surfing back and forth in a few lessons), where you are "planing" from the start. You can go kitesurfing in far less wind than you need for windsurfing. Your kitesurfing kit takes up a lot less space then your windsurfing kit, making it easier to store and to travel with it.
Comparing pickleball to tennis is sort of the same. With tennis, you spend the first months mainly picking up balls that you missed or hit off court. It takes some time to be able to play some rallies and even more time to get good at playing matches (where the serve also comes into play). I never played pickleball (i am from The Netherlands, we have padel here), but if you compare it to padel, it too is a lot easier to get into. The court is smaller (even has surrounding walls when playing padel) so you don't have to chase your balls that far. The technique involved to be able to play a match is a lot less easier than tennis. It is also more of a social activity as you are closer together and playing more doubles, so you can chitchat more.
When i go windsurfing now in my late 40's, i am one of the younger guys at my spot. A lot of older guys, retired or close to retirement, and some youngsters (mainly the kids of the windsurfers willing to give it a try).
When i look at my tennisclub, i see it is more mixed, but also a lot of older people and their children starting tennis. All the "new" people who want to start with racketsports mainly start to play padel.