pug
I agree, with your first statement, until recently, guys in their 40s, 50s, and I even knew 1 guy in his 60s who got into a regional jet! So it WAS happening. C-19 has probably changed all that for the next 5 years at least, although it is possible that some airlines may see opportunity in less experienced guys in their 40s/50s, as they may be more likely (than experienced pilots) to accept poor working conditions in order to get their shot. However in general I think (and hope) that they will choose experience over newbies when the time for hiring comes around.
I am curious about your last statement, what would you say are worthwhile ways to keep current whilst waiting for the hiring cycle to begin again?