It may be a problem with EU regulations. It’s hard to see how Apple could be certain they had complied with the EU DMA law, given its based on vague outcomes rather than clear requirements with extremely large penalties. The fact the EU was only willing to require the DMA regulations be met by large foreign companies doesn’t inspire confidence.

And it’s not like there is a thriving tech ecosystem of successful EU tech companies showing how it’s done. So there is a lot of ambiguity on how companies can reasonably comply without huge risk of 10% global revenue.