Epic tried to do that, but Google made secret deals with OEMs offering them a cut of play store revenue if they don’t (https://www.theverge.com/2021/8/19/22632806/google-epic-prem...)

Part of the deal was that they couldn’t tell anyone about it without Google’s permission. So when you get a rejection from an OEM after you offer to bundle your store, you don’t get an explanation.