I turned 70 during COVID, & 71 a month ago. Getting back to the newly reopened dojo is certainly being a challenge. I lost a lot of ground. But I go and do what I can. This is an Aikido dojo. I started when I was 65 with no prior martial arts experience. I'm with Carol Lennox. Aikido is a good one to get into when you are old. Among other things it teaches you how to fall.
All that said, these kind of gung ho articles are beginning to cringe me out. I can't quite explain why. Maybe because I suspect that my 70s are not going to go like my 60s. For one thing I am not looking forward to living to see the end of democracy in America.