Perhaps people want the ability to choose between fully featured app stores, because of things like these
https://arstechnica.com/information-technology/2020/01/resea...
https://blog.trendmicro.com/trendlabs-security-intelligence/...
https://www.techrepublic.com/article/new-android-bug-targets...
https://www.zdnet.com/article/popular-apps-on-google-play-li...