I can't speak to your situation, but I know that in mine the main blocker for a LAN party with adult friends wouldn't be a lack of interest nor lack of friends (though I don't have a giant pool, and can't even count 18 people I'd be able to even suggest such a thing to) it would be lack of time due to other life responsibilities, that tend to increase as we get older.
My solution has been to play boardgames remote using BoardgameArena[0].
I usually have 2x turn based games going with two separate groups along with a dedicated chat channel, and then do 1-2 live evening sessions over video call with other groups. But all setup to be flexible and made to fit with the constraints of adult life, so sometimes we play and sometimes we reschedule.
My solution has been to play boardgames remote using BoardgameArena[0].
I usually have 2x turn based games going with two separate groups along with a dedicated chat channel, and then do 1-2 live evening sessions over video call with other groups. But all setup to be flexible and made to fit with the constraints of adult life, so sometimes we play and sometimes we reschedule.
[0]: https://boardgamearena.com