Server side only anti-cheat is one of the problem domains that I'd really love to work on at some point in my career. This is the type of adversarial arms race that just seems really fun to think long and hard about.
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Because they're 10 years behind the curve and don't understand that a game's lifespan is contingent on anti-cheat. Once it becomes clear to the casual player that a hacker is going to effect every gaming session, the game dies quickly. Many games have gone so far as to obfuscate the presence of hackers so that players are less likely to notice them (CoD)! Other games build from the ground up with anti-cheat in mind (Valorant). Other games have an ID verified 3rd party system for competitive play (CSGO).
Personally, I think there is a middle ground between root level hardware access, and treating cheating as an afterthought. I'd lean more heavily on humans in the process... Use ML models to detect potential cheaters, and build a team of former play testers to investigate these accounts. There is zero reason a cheater should be in the top 100 accounts; An intern could investigate them in a single day! More low hanging fruit would be investigating new accounts that are over-performing. I'd also change the ToS so legal action could be persued for repeat offenders. Cheaters do real economic damage to a company, and forcing them to show up in small claims court would heavily de-incentivize ban evaders. This probably sounds expensive and overkill, but in the grand scheme of things it's cheap; it could be done on the headcount budget of 2-3 engineers. It'd also be a huge PR win for the game.
Or you could spend a huge effort on cheatproofing only to find that no-one plays your game in the first place, e.g. Concord. I imagine getting cheaters in your game often falls into the "nice problem to have" category and it is easy to kick the can down the road.