Do what the Chinese did and fork Android.

The EU has enough tech talent to do it, but the political and managerial class lack both the strategic ability or the willingness to adequately reward the effort it would take, almost certainly preferring to, again, outsource the concern, and then be shocked Pikachu later.

Anyone doubting this should see how BMW think about their in car software. And that is for a supposedly premium product.

They can make the product according to rules that are imposed on them. One rule: allow privacy. Unless the privacy is not in the field of interest of both the producer and the EU

They can’t force someone to make a product, but they can force someone to choose between making a product or exiting the EU market.

In practice they’re the same thing.

While the EU and its member countries can't (or at least morally shouldn't) force people to make the product, if it was a priority they could incentivise it with funding, tax breaks, etc.

They could give more funding to SailfishOS, for example