By that point the player base can already be devastated, and it can kill the game. Cycle: Frontiers was an extraction shooter, and the immediate cheating was rampant; the game's design meant dying to hackers was devastating -- imagine a hacker forcing you to lose not just this game, but retroactively making you lose the prior 5 games too. This absolutely destroys player morale, near instantly. Even if you ban that hacker instantly, there's an extremely high chance those players will never return. Because the rampant cheating went on for so long, the game's reputation never recovered. Within a year of release the servers were shut down.

A single cheater can often ruin games for hundreds or even thousands of players very easily. For experienced players, seeing a single flying aimbot shithead in your lobby just means there are 10 other cheaters in the lobby too -- ones using subtle ESP/wallhacks that can be extremely difficult to detect, by design. Shady websites like G2A or GMG that sell keys (which are almost 100% hot keys, to really make it all come full circle) mean that even if you get banned, buying new keys for a new copy of the game is extremely cheap, especially when many of these games have items that can be sold for IRL cash in various ways, games like Rust. For many parts of the world, selling/trading rare items to players can net you plenty of actual income -- and getting banned means nothing as a result. Instant banning cheaters the second they are confirmed leaks information to the cheater and cheat creator, today most games like Warzone or Destiny have to play psyops and shroud their exact detection techniques in part by doing "ban waves" only when they accumulate a mass amount of confirmed cheaters. The cheater that ruined your top score may, necessarily and by design, be allowed to run free for a while.

The net result of all this is that designers and -- importantly, even though people on Hacker News don't want to hear it -- PLAYERS tend to overwhelmingly prefer prevention instead of reaction. They are both needed. Players are not morons who love installing rootkits. But on the whole, preventative measures tend to be more valuable to players and creators than reactionary ones, even if they are all ultimately imperfect.

In a funny twist, games like Tarkov and Rust do have a gameplay mechanic that reduces the long-term psychological devastation of cheaters and is not invasive at all: they reset all content in the game to "neutral" every once in a while, so basically all your stuff gets deleted, and everyone starts over again. (This non-permanence is probably one of the reasons players stick with the game, despite cheaters, which are incredibly infuriating.)

Can I ask if you seriously play any online competitive games, at a high level or otherwise? Because I do, and I'll be honest: I've been hearing it all for 20 years. These types of approaches have had success (CS's player review system, certain shadowban systems, "trip wires" that trigger on impossible game behavior), but there is no single approach that has proven itself to be the ultimate universal solution. There is no universal, wibbly wobbly bullshit stats algorithm you run on your servers to "solve" this. These problems are not solved. I don't like it. I don't run certain games with certain forms of anticheat. But it is what it is.