Compatability has to be in the core in some form.
To me theres no realistic way without compatability.
I gave up on my ubuntu mx4 and now use the mx meizu flyme android because of............the money.
Not linux/Android/freedom, like/dislike discussions, but simply because I would have to have two phones: To operate with my banking, reading danish newspapers, see danish television, use the danish mobilePay, use the phone with online ticketing for bus/train - a lot of stuff that has nothing to do with "hobbyist" fiddling with philosophical linux/windows/android speculations but all to do with very everyday digitalizations of very soon everything in daily life.
And all those local institutions in all countries are NOT going to create linux compatible versions of their apps.
But they are going to be even more necessary to have access to.
That leaves the discussions with no choice - if the UBport is going to be anything else than a utopian/idealistic project, it will have to cooperate with a lot of android apps.