Of course, both can be true.
Women over 50 may be the fastest growing group amongst runners, but the competitive ranks do thin out as we get older. And those running in the over 50 group may be the same runners who were in the younger age groups, but have gotten older.
In terms of lifting weights, I’ve competed in several meets and there’s only been one woman and she was 80+ years old at the time. And she only deadlifted.