Quake doesn't appeal to a casual or competitive audience anymore.
Casual gamers will play games that are popular and that are easy to get into (content creation for video games is a HUGE factor). But since quake is neither easy with its high skill floor and ceiling or is massively popular so that you can have more balanced matchmaking, you end up with new players being curb stomped and quitting.
If you are a competitive player the question you need to answer is: "Why would I invest my time into quake, when I could invest my time into any other competitive FPS game and get x100". Like why would any 15-16 yr old spend time grinding quake - when they could grind CS, Valorant or Apex Legends?
They would get more opportunities, more LANs and more money. For less effort, as you could collect a paycheck in T3-T2 CS or you could try win a LAN against rapha for the same paycheck. Plus, a player can shift to streaming/coaching/casting/analyst/content creator if it doesn’t work out.
Now there are a few new players and an older audience who will be able to deal with these problems because they end up finding the game very enjoyable. But the franchise is dead in the water at the moment. Honestly, I don't know how they would fix these problems.