There's already a compatibility layer and it works really well. Most android apps run fine on Linux. The big problem is Googles security layer which is also what causes problems for alternative Android builds like GrapheneOS or PostmarketOS. That prevents you from running certain apps (mostly banking but notably also includes Google Wallet preventing tap to pay) on devices with unlocked bootloaders as well as Linux. Any non-official version of Android, or even an official version running on a device with an unlocked bootloader is going to have a problem.
Beyond that having tried a Linux phone as of a couple years ago it had significant usability problems such as unacceptably high battery drain and the inability to receive push notifications when the screen was locked. Some of these issues may have been solved since the last time I tried it, but at the time the experience wasn't one I would recommend to anyone nevermind the average person.
The tricky part here is that many of these reviews aren't about how they feel about the game but rather how they feel about the developer or publisher, often based on wildly inaccurate speculation. Valve has a particularly tight rope to walk on this one because it does seem problematic to dogpile some game because of a perceived opinion that has nothing to do with the actual game itself.
One possible solution would be to add a category system to reviews that let's reviewers correctly categorize their reviews, purchasers exclude categories they don't care about, and Valve only removes miscategorized reviews. Categories could be something like "game contents", "game bugs/technical issues", "drm", or "publisher/developer opinions". Maybe make an entry form on the review itself for each category and you can just leave any category you don't care about blank in your review.
This might also help solve one of the more long standing problems with Steam reviews which is that reviews of early buggy builds often linger long after those bugs have been fixed and can provide a somewhat inaccurate impression of the current state of the game.