So I've only used playstore and chrome so I assume everything else ain't that important. Chrome can be replaced easily with Firefox if what you say is true that it cannot be blocked. I'm not a software engineer but it doesn't seem too hard to make a playstore, which is basically listing a bunch of apps you can install. It's access to the apps themselves that is important, not the playstore you go through.
If one can grey-zone side-load Google's stuff into a Huawei phone and there are easy mods to make Google apps unable to detect a Huawei device then Huawei can keep the global techie market that revels in what a Huawei premium phone can do and know how to keep the device running the way they want (or at least can get someone to do it).
If Huawei can legally side-load most of Google services into the phone OR they can come up with an easy-to-use domestic alternative to getting those apps working and basic functions performing, then Huawei can keep most of the global average Joe/ soccer mom market.
If neither can be done then Huawei phones are coming back home to become self-sufficient before they re-expand.
An alternative open source appstore like this?:
I checked their website and they have common google apps on there:
This would be a good stop-gap until Huawei creates their own appstore.