Is it ever too old to start gymnastics?
I’m no expert, but it would seem to me that there is no age limit to begin. But, unless you start when you are a child, you’re probably not going to be competetive.
If you really have taken care of your body, no. But you should be strong and flexible before you join.
The flexibilty, agility and conditioning work should be good for anyone. If a 60 year old man were starting, I wouldn’t expect him to be doing the splits and double twisting back tucks. However there is no reason why he shouldn’t be able to take and benefit from it.