That's not at all what it is about. If that's what it was about, why on earth would Windows, Google Search and Meta be considered gatekeepers? A lot of people think they are pro DMA because of all the App Store stuff. Most people have NO IDEA how far reaching it is. The App Store stuff is one small part of of the DMA. At its core, the DMA is ultimately an attack on the concept of big tech companies being able to vertically integrate to give themselves a competitive advantage. If they want to create a cool new feature, they have to provide others the ability to do the same.
As noted several times on this and other threads, while I realize I am in the minority of MacRumors members here, I think it's a really stupid way to do it, that has already and will continue to make products worse for EU citizens. But ultimately if EU citizens want bureaucrats designing how tech software works, that's their prerogative.
But then EU citizens don't get to be outraged when Apple (or another gatekeeper) doesn't want to release a feature in the EU, whether that's because they want assurances from the EU they're allowed to release the feature, need more time to refine an API before they make it public, they have security/privacy concerns about making an API public, or even because Apple wants the feature as a competitive advantage. That's Apple's right.
It doesn't mean they're being spiteful. In fact, Apple has a fiduciary duty to their shareholders, and they would be negligent to release a feature they thought has a significant chance of running afoul of the DMA when they can be fined 10-20% of global revenue in a market that represents 7-8% of their revenue.