With all given respect, but you knew that you bought a telephone from a startup company that is completely dependant from its suppliers. Furthermore you knew that the Android update situation is less than optimal with all manufacturers.
For such a small company Fairphone did extraordinarily well in supplying security patches. They even got hold of the source code for the totally blobbed Mediatek Android - something different manufacturers wouldn't even waste a thought about.
Really, get to your senses. Different Android phones don't do any better.