Servant of Cats wrote:
I don’t think there is an EU requirement to allow side loading of any old app from any old source (including possibly malware apps or infected apps).
I was under the impression that Setapp Mobile is exactly that and only available in the EU. Here in the US we have their similar platform for downloads on the Mac and the site is filled with questionable apps that install processes in the launch folders of the Mac that have been problematic with unknown content identified by Little Snitch being sent to their servers. The apps range from the typical cleaners/optimizers to what I would consider to be shareware/freeware from back in the day.
https://support.setapp.com/hc/en-us/articles/13690464925212-About-Setapp-Mobile
AltStore PAL is another one that is a collection of different apps, not specific to a big game company just offering the service without Apple's cut.
https://altstore.io/
I am not in the EU so have no direct knowledge on the quality or experience of these App Stores, so maybe you have additional insight for a user looking here that may have concerns about privacy/security of their device. Is it enough to say they do not have an incentive to distribute malware when the developer pays them to make the app available?