How is this different from good (non-cheating) players joining a new website and having to get to their realistic rating? This happens, but as a percentage of games you play it has a very low impact; moreover, platforms usually tell you that a player has a not-yet-established rating with a question mark, eg 1620?

My suggestion is to just stop thinking about cheaters when playing online rated games. I started doing so years ago, and have increased my enjoyment of the game A LOT, without any visible downside.

Yeah seems like a trivial issue to fix - first 10 games are for evaluation, heck they can be had even against computer. Very few people are so pathetic/psychopathic to invest so much time into getting a rank and then cheating on real opponents and tank their account quickly. And for those few, just don't care about them, its just a game after all.