So how can you join in on the fun? First, you'll need a retail copy of Freespace 2 ($10 on GOG and Steam). And for newcomers, the original campaigns are available with updated graphics and they're still amazing.
I'd start with those to learn the ropes. Like most sim games, the control scheme for Freespace is extensive and complex, with dozens of hotkeys and at least 20 commands required for regular play. (Unlike many sims, this one probably plays best with a mouse, leave the flightstick under the desk.) Apparently these are all muscle-memory for me -- I was able to jump back into the action, simultaneously adjusting my shield power while cycling primary weapons, engaging afterburners and targeting the ship attacking my objective, without a sweat.
Beyond the original campaigns, dive into the mod work and try Inferno Nostos, The Procyon Insurgency, and Wings of Dawn (though skip the cringey, optional, NSFW files for that one). The best fan-made campaign and, one of the most impressive mods I've ever seen, is the staggeringly ambitious Blue Planet. It's essentially a whole new game, a pair of massive campaigns covering 50-missions with entirely new weapons and ships (and with serious Battlestar Galactica vibes). Or if you'd prefer full Battlestar, there's Diaspora, and Beyond the Red Line, a pair of multi-campaign total conversion mods set within the world of the Syfy Battlestar Galactica reboot. For fans of 90's space sims who feel left out, there's even a full fan-made Wing Commander game with 50 missions on offer. If you miss space sims at all, it's the best $10 you can spend.