Admitting a typo isn't making your case either. Do you think you can be in a pact/bloc like the EU with its various and far reaching trade policies and other connected affairs, and not need to negotiate terms when you leave!? Thats got nothing to do with whether the country in questions sovereignty has been compromised.
I guess it comes down to how you define sovereignty. If you consider it to include, yea, we gave up the right to control certain aspects of how we operate as a country but are still a sovereign state; then fine, I would consider that still sovereign but a more limited sovereignty. Which is back to my point, member states have surrendered some of their sovereign rights to the EU in exchange for membership.
Which is why I disagree with your statement:
There is no loss of sovereignty in the slightest.
To get back to the DMA, if a member country decided to tax all sales by any App Store in that country under teh guise of an "infrastructure tax" and rebate it to Apple as reimbursement for Apple maintaining critical infrastructure for teh smooth running of all app stores and ensuring access; I suspect the EU would react negatively and it wind up in court, much as Ireland did with their tax code.
A fully sovereign state would be free to tax and use that money in any manner they see fit; however iI doubt the EU would be happy with such a (very hypothetical and unlikely) scenario.
To be clear, my position is not that EU members nor US states are not sovereign entities; just that they have given up certain sovereign rights in exchange for being part of the EU or the US. The conditions under which they are governed is different in some was and similar in others.
And by the way, if you did know about what you were talking about, you would know that it would have been perfectly possible to just withdraw and slam the door shut, as very nearly ended up happening. It just would be a terrible idea.
Yes, I realize they could have since while article 50 says a while withdrawal is to be negotiated, it also states it is effective in two years if no negotiated agreement occurs. IIRC, the UK and EU extended the deadline so as not to simply have the UK leave since both sides realized the mess it would cause. Had they not, the UK would likely have been out with no agreement, which would have been much worse than what is now the case.