> I believe it was the Apple fee monopoly that was the central thrust of the anti-trust case, not open distribution of apps themselves.

This was not just subject of the anti-trust case, it's Apple being expected to comply with the EU Digital Markets Act.

(The DMA defined objective criteria to identify a scaled market of digital goods with an uneven playing field for all players. Apple was found to have created such a market and was ordered to rectify this)