I doubt, AABs are only proposed as an incremental update option rather than a replacement of APK model. APKs can and are built, considering most companies want their apps to be usable inside of Google banned countries, and for small devs the AAB option is harmful for distribution. I also read that AABs can also be used to disperse installations across various architecture platforms and DPI screens as well, so this point could be somewhat concerning, still not as much. Correct me if I am wrong.