Apple is in a position where they can't expect everyone to be happy with iCloud, which is great because it means they actually put effort into supporting (decently!) a range of third party services. Siri generally isn't as smart as Google Assistant, but it also isn't completely obsessed with Google services. That is to say, unlike Google Assistant, every app on my phone - without exception - actually knows what is on my NextCloud calendar. And it actually gets useful information from my email to do helpful things with.
On the other hand, if you look at how Android has progressed over the years, I think Google has been trying very hard to forget about Android's past as a flexible operating system that exists outside of Google's ecosystem.
