I see people in Vibrams and Vivos at the gym all the time. I wear nothing but minimalist shoes (since long before the hype, I was the barefoot kid where I grew up in the 80s/90s), so maybe I just notice it more?
Quite frequently people will come up to to me to ask me about my shoes, so there's definitely an interest.
Excellent article. I wish more old people would pick up weights. What often keeps me going to the gym is the knowledge I want to be strong when I'm old.