It's not that unusual for people to pick up e.g. powerlifting past 50 and still get to levels well beyond what most younger adults can lift.
I'm 51, and recently back into powerlifting after many years out of it, and I certainly expect to build back muscle and improving week over week for many years before I can't stem the decline any more, as long as avoid injury or health issues that takes me out of the gym - avoiding time off exercise is the biggest challenge with getting older.