In my opinion, yes they are kids (unless it's their business), there comes a tipping point where the kid has to decide whether to stay kid and keep on doing these mods, or to step up and buy something reliable and fast from the factory and focus on other bigger things.
In case of PC modders, rather than modding the heck out of a system again and again, after a while when they have done all sorts of things, they should simply buy more expensive components and get best performance they need out of the box. Actually freeing their brain from this never ending tinkering, at this stage you only upgrade to top of line parts every few years, so your hobby is still alive but it's not eating all of your time, by doing the same thing over and over again.
Similarly in car modding, you start with something mediocre, you do the mods get the experience, and now what? You can keep buying these budget builds and make them faster by doing all sorts of mods, but then comes a upper segment car which beats your car with stock factory tune, locking you in, in your own segment. After you have done this tinkering you simply buy an expensive performance segment car and be done with it, now your brain is free to move to a bigger thing. You buy another performance car when the right time comes, but you don't mod now, because you have been there, done that.
What bigger things you might say, well there are plenty of things, it could be a another niche or mainstream hobby ready to be dominated by your brain or you could simply scale your existing thing and make it larger, for example providing a service of your expertise for money or for free, etc
Gist of the matter is you don't want to spend most of your life doing a same thing over and over, except your job, other than that you want to experience as many things as possible. Flashing a custom ROM over and over is definitely not one of them.