It's not entirely a contradiction. De-Googled Android alternatives can give a perception of choice and also a perception to Banks that they support "everyone" at the same time. "We have both flavors, Vanilla (iOS) and Chocolate [Android]; you claim to want Chocolate (Android), what more do you want?"

Absolutely the current duopoly market is going to make any third-party alternative harder, but de-Googled Android seems to be a worst case because "Why not just install Google Play Services?" remains too valid a question and has too many confusing answers for both non-technical users and the business people at application providers (banks and whatnot). They will continue to have a hard time trying to figure out why you keep asking for a harder work effort for Chocolate Fudge when they already have Chocolate and why isn't that good enough.

It's easier to fix that confusion by asking for an entirely new brand/flavor, such as Strawberry, than continuing this increasingly hard war between Google's Chocolate and "free" (as in speech, but certainly not free of confusion) Chocolate Fudge.