The vast majority of people just vote down predestined party lines, and swing voters aren't all the bright educated people we like to think they are. It's just a fact that half of all people are of below average intelligence.
Politicians should be a better than average cohort for intelligence, but judging by the incomprehensible jabber they espouse on tech matters I doubt it'll change anytime soon. They seem to spend most of their time trying to dick each other over and make themselves look good rather than actually get shit done.
The importance of a debate like this is it allows the various parts of our governments (and their bosses: us) to state their positions and work out a solution. What that solution is is not a foregone conclusion in the least (cf. the Clipper Chip, https://en.wikipedia.org/wiki/Clipper_chip)
Clearly they never had problem with that. The problem they have is that it takes NSA up to 8 months to crack a key for one single iPhone, and the list of crack-awaiting devices grows every day.
That's is what they are truly complaining about and as others pointed - they try to use this case of supposedly pro-terrorist Apple to force them to give out the key that would open any and all other I-devices.
I bet a bottom dollar if Apple asks to hand the device and they will retrieve info off of it, FBI would come up to every possible excuse -- including the one that the cannot trust Apple employees -- not to hand it over. They want the KEY, not any other way around!