you misguide to the wrong assumption, that also all others HW-I2C must be identical ?

It isn't !

where did you gtet that impression?
I even said "SILabs derivatives (forget the deviates)".

Now, why do you state, I distill your statements to this, "processor efficiency does not matter if I can use code I already have".

Of course, if you make one-offs then dev time becomes an overwhening issue and you may, in that case, have a point, but beyond one-offs where does programmer time (1 day vs 1 hour)become more important than processor efficiency.

I can see many cases where "canned code", even if a bit less efficient than custom, can have a place, but bit-bang is a true processor time hog which put it in a totally different class.

Erik