At some point, you have to just recognize that the world is different today. The general market has accepted walled garden OSes with anti-competitive behavior towards common applications.
Apple doesn't have that kind of market share to warrant it. Tangentially, Apple products are aspirational, so they never won't have it, that would lose the appeal. Microsoft, on the other hand, pushes their products every way imaginable, and many of their users use them because they have to.
If you're looking for reasoning/justification behind why Apple got away with something like this, blame the government agencies for not doing their jobs.
IMO, it's slightly unfair that Microsoft got hit with that lawsuit back in the day. They 100% deserved it, but it put them at a disadvantage some years later against all of the other monopolists in the tech industry who were not being scrutinized for doing the exact same (and worse) things.