Interestingly, I brought this up with some IFATC people a few days ago.
Basically, I read an article that @Maxmustang posted regarding when it is appropriate to report “unable.” From what I hear, pilots mainly use the option to disregard perfectly reasonable commands.
Anyway, at the bottom, I found this:
What I got out of this is an added option to the unable button. For example, if a pilot reports unable, they’ll be required to say why, and given the options of “terrain,” “traffic,” etc.
I feel like this new add on would definitely improve pilot communication with ATC, and help weed out the ones who just want to follow their flight plan.