The main thing is, the vast majority of people don't actually want open world PvP. They want bite-sized rounds with well defined goals. If you want to see examples, take a look at stuff like DayZ or Rust (open persistent world) and then look at PUBG. Orders of magnitude more players playing PUBG because you play a round in no more than 40 minutes, and nothing you did affects you going forward other than cosmetics and you maybe got better at the game.
Same with WT. You play a round that is theoretically set up to be "fair"(Krusty's points notwithstanding), you either win or lose, you earn some points toward the next thing you want to buy/upgrade. In 30 minutes or so you have done something with a beginning, middle, and end and you can see you made some kind of progress for something.
As far as the flight model, airplanes in WT basically range from slow and turny to faster and less turny, and they stall if you get them too slow, with varying levels of upgradeable guns. This is enough for most people. They don't want the Ensign Eliminator modeled correctly or flat spins, because those things don't add to their feeling of being an awesome game pile-it.
And regardless of if they're serviceable, at the end of the day people want graphics. It doesn't matter to Aiden with the $3000 alienware and 32" 144Hz 4k display that you can have over 100 planes on the screen at once. All that matters is it doesn't look as good as the next game over.
That's why this is and always will be a niche game. At the height of popularity, IMO people were tolerating the parts of the game that they didn't like to get the stuff they did. It seems to me lack of instant action is likely one of the main things that they were tolerating. When options came along that looked better and gave them the instant action, they vacated.
At least for me, instant action isn't what I want out of this game. What this game provides when it has numbers is what I want.
Just MHO.
Wiley.