Quake 3 is objectively the best game ever, now and in 10000 years. Having stablished this fact, what is needed is to set a golden stardard like chess. Eventually the masses would wake up to reality and they would "click" and realize the people they've been calling "pros" are in fact noobs. Their idols would be fools that get destroyed in a real game.

What im saying is: Drop the failed QC experiment, take Q3 as the base with perfect aesthetics (varied, with both high-tech and dungeon-ish stuff convined that somehow works) and perfect balance of fast but not too much (VQ3 vs CPM/QW) and perfect engine (all other engines have annoyances: Q4 felt cramped, QW had the annoying stairs that stopped your flow and was too brown, Q2 had the weird looking models and it just didn't feel "e-sporty" like Q3, finally QC is a mix of everything bad in between, knockoffs like DB will never be Quake).

Basically, assume this is a niche for 800-1000 players at best, this is higher than the 340 players of QC right now which stopped playing Q3/QL because they were forced to move to QC to find some matches and the rest left when forced to pick a champion and deal with the shitty engine.

Those 800-1000 people are the core of the game and you reduce it everytime you release a game that isn't Q3 with an updated engine (without changing the movement feel, just visuals etc) to further stablish an inmutable standard of duel/TDM.

However, here is the catch: that doesn't stop you from trying to pick up a share of the masses. Everytime there is a trend, you can capitalize on it without having to release a new f*cking engine that is worse than Q3, you just add new gamemodes. (Hint: Epic will never release a Fortnite 2)

So here is my idea for the new gamemode: A Quake Arena battle royale where people jump from and fall into the arena, pick weapons and so on as usual, try to survive until the end, but here's the twist: The last 2 standing players enter into a duel and everyone else is spectating, those spectators can place bets on who will win to incentive they stay until the end of the match. Find a way to make use of said tokens, hell or even allow Bitcoin bets with lighting network. After surviving the battle royale, then the epic ending with the duel, the gambling and so on, would bring the tension of dueling which is the only gamemode that can give you these feelings, all in the best engine and aesthetics possible time tested across a million years.
Add in rankings of how much people have earned, lost, as well as an ELO system.

Organically it would pick up players. Invest in assorted twitch streamers to get the ball rolling. People love seeing stuff when money is involved, the gameplay and aesthetics of Q3 would do the rest.

What id has is the power of having The Golden Standard of dueling for the next 10000 years and they keep fucking it up because they don't know how to take the right steps. They just keep fucking things up, now in the form of QC.
If they did what im saying, they would have a core playerbase higher than the 340 they have now, it would go back to 800-1000 players, slowly would pick up more players as the highest the core amount of players is, the highest chances of exponential growth as per metcafe network distributions. The future is crypto betting in game and there is nothing more thense than a Q3 duel with money involved, the battle royale aspect just adds a fun/casual aspect to it before the final showdown resolved in the duel. This would pick up people slowly. It's a long term investment.

You have the brand, the gameplay, the aesthetics, and a loyal small playerbase enough to keep at least these needed small amount of people playing to reach organic growth. Use it properly.