'I'm not able to devote extra time and resources to develop m/m paths...'
I don't think PierreStorm was asking about why extra time and resources aren't being invested to include content that isn't present in the game.
If I am interpreting their question correctly, they are curious about *why* m/m content was not part of the game's original design.
Upon reading the developer's answer, I must confess I am now quite curious about the specific reason too.