I hear and observe that a lot too - that the beard becomes an essential component of an older man who wants to remain attractive regardless of what the trend is. It's as you say, disguises skin and looks deterioration and can make someone look a touch younger. Now with the trend, they all have it anyway. You can see how terrible Elton John has looked with his combover, fake dye and clean shave over decades, he's always looked like a grandpa for 20 plus years and now he looks so odd.
As a younger guy with a masculine defined face, beard on/off makes little difference in terms of attraction imo but following the fashion does give bonus points because of how girls are currently conditioned - and they will like you more for it and it will not suddenly transform you to into a middle aged man lol. Sometimes I see (online of course) that a beard ages a young guy, this is loosely thrown around by men who can't grow one or are already old looking/old - a truly young looking man will always look fresh with it or without it as long as it's an appropriate size and trimmed well not to mention the benefit of fashion and facial sculpting for those who need it.