Cirrus App dev pulling app from certified android devices in '26/'27

https://discuss.tchncs.de/post/45277582

How easy is it to convert an Android app to a Linux mobile app of you’re the developer? If it’s written in JVM languages it shouldn’t be that hard right?
Just use a custom ROM. This sadly will affect app developers. But if you are on a custom ROM without GMS it will continue to work just fine.
Google is trying to kill custom ROMs too. Also I thought the majority of modern phones aren’t bootloader unlockable.