What I'm getting from this discussion is that what the community ultimately wants is not just MORE players, but more QUALITY players. This is a funny game, in the sense that I regularly see rather highly rated players completely beating themselves up in the chat over how bad they are. There's a unique level of acknowledgement of how difficult this game is, but also how enjoyable it is, even when most of us aren't that good at it. And so everyone wants everyone to get better, so that we can all get more from this game. So that's a good place to start.
So my own views on the issue, as someone who's sorta new to FAF (tried playing it over the years but got completely humiliated and ran crying back to vanilla SupCom skirmish vs CPU where I could satisfy my addiction to the pause button in private).
First off, the attempts to educate players need to improve. It's easy enough to find tutorial content, but it's hard to find the RIGHT tutorial for a given skill level and skill deficiency. This is a common problem that exists also in music education: the best guitarist in town is not necessarily the best person to teach you how to play guitar. I find the tutorials in the FAF application to be useless to someone of my skill level. "Build a Land Factory, 2 pgens, mex, pgen, mex, pgen, mex, mex" or whatever it is. OK, simple enough, you're scaling your power production to meet your needs. Then it gives you this list of units to build from your land factory that a new player would have no chance of memorizing or understanding the logic behind. It's just way too much for a "first tutorial" and it feels to me like it was created by a player with very advanced skills (best guitarist in town) that just assumes that everybody understands very basic things.
And so these discussions about a "noobie ladder" and the Stoneage mod and other attempts to make better matchmaking are valid, but I think that if what the higher-ranked members of the community want is more skilled players to go up against, they really need to invest more time and energy into education, and I think the first thing they need to do is find someone who's good at making tutorial content, because that person is rarely going to be one of the better players (those who can't, teach, right?).
Beyond that, I think the Stoneage mod is a good concept that could be expanded on. It immediately made me think of promotion and relegation in soccer. Maybe there needs to be ladders for every tech level, and maybe you need to play yourself into a promotion before you can play ladder games at higher tech levels. Maybe the current 1v1 rankings can be used to initially slot players into different "leagues", but after that it should just be about who you beat and who beat you. If player A is demolishing everybody in the Tech 2 league and player B is getting walked on by everybody in the Tech 3 league, it doesn't matter what their rankings are: player A deserves the opportunity to go up, and player B needs to go down to make room. Something to think about.