EU isn't forcing Google to let random 3rd parties replace Gemini AI with TotallyHonestAndNotStealingYourData Corp's AI.
You already can replace the default assistant app with any app that declares itself as an assistant on Android, and have always been able to.
Google is a designated gatekeeper carrying all the same DMA obligations for:
Google Search, YouTube, Chrome, Shopping, Maps, Ads, the Play Store, and Android.
https://digital-markets-act.ec.europa.eu/gatekeepers_en
You can replace Gemini with Perplexity or whatever you want on your Android phone, that includes the main system-wide assistant.
You already can replace the default assistant app with any app that declares itself as an assistant on Android, and have always been able to.
Google is a designated gatekeeper carrying all the same DMA obligations for:
Google Search, YouTube, Chrome, Shopping, Maps, Ads, the Play Store, and Android.
https://digital-markets-act.ec.europa.eu/gatekeepers_en
You can replace Gemini with Perplexity or whatever you want on your Android phone, that includes the main system-wide assistant.