Give me a Reason

In this point you are right, but some users might say that it is good to have the choice in Android to choose between different clients (and also different features).
And in Android most KeePass variants are for free.

I know this other topic, I have posted it in May 2018 (2 1/2 years ago).
It has 347 votes and is the 5th most voted feature:

But I am not sure if the API-way will work with all applications (I posted this question already in that topic).