My mother lives in a very large Floridian retirement community and my observations while there definitely support what I read in this article.
They have semi-legit gyms for everyone to use as part of the association membership and I've spent some time in these. No squat rack, but they let me deadlift and have dumbbells up to 50. They actually have barbells and a bench press too. Lots of different machines and a smith machine for squats. Not too bad for a retirement community.
In these gyms I've met quite a few 65+ people who are in phenomenal shape and they are hitting the weights hard. One of them even got excited when he saw me deadlifting because he didn't realize they even allowed it. As an aside, I was only deadlifting 275 the last time I was there, which was a year and a half ago. They had ceramic floors and rubber-coated plates, so they held up fine. They may not take too kindly to my methods if I were to start banging 550+ pounds around.
Anyway, these guys know what's up, and that's why they are going water skiing next weekend instead of playing shuffleboard.