Edit: OK, the term “gatekeeping” is all over the wiki concerning the DMA. But as is often the case, a term can have different meanings in different legal contexts. In Apple’s case it looks like the DMA was more about Apple opening up the browser, NFC payments, and favoring their own apps in the App Store. I don’t see anything in the Wiki about sideloading as part of being a “gatekeeper.”
> Example of the “don'ts” - Gatekeeper platforms may no longer:
> treat services and products offered by the gatekeeper itself more favourably in ranking than similar services or products offered by third parties on the gatekeeper's platform
I find it hard to see what is not 'more favorable' about staying within the walled garden. All their rules are made to terrify people that would step outside it.
At least that's my reading of it.