I genuinely believe with all my heart that Sinmir is the worst man in all of Whiterun.
Nazeem is a smug, arrogant prick. I'm not disputing that, but at least he has a life. He runs his own business, owns property, and he is married. If nothing else, he is a functioning and actively contributing member of Whiterun's society. Sinmir is just a fucking dork that LARPs as a tough guy. He has no job, no home, no wife, no responsibilities, and no accomplishments. This absolute bum spends his entire day and night inside the Bannered Mare, talking shit about the guards and the security of Whiterun.
Brother, you are sitting in a tavern wearing FULL IRON ARMOUR while other people do the job you pretend to know anything about. What could you possibly be preparing for? Mikael getting out of hand?
What does Sinmir actually do for Whiterun? The city itself is surrounded by threats. The tundra is littered with bandit dens, giant camps, and all kinds of dangerous creatures. You are effectively in mortal danger as soon as you step out of the gates. Is he joining the city guard? No. Is he out there patrolling the roads? No. Is he clearing out those bandits? No. Is he protecting the smaller settlements? No.
Whiterun is already stretched thin dealing with a civil war and dragon attacks, yet Sinmir is too busy aura farming in front of civilians to lift a finger. God forbid he actually takes that FULL IRON ARMOUR outside, gets his hands dirty, and backs up all the shit he talks from the safety and comfort of the Bannered Mare.
Now, let's say I want to give him some grace and believe he just wants to stay in Whiterun so he can be on hand should anything happen. Well, he had the perfect opportunity to prove it.
A dragon attacks very near Whiterun at the Western Watchtower, and the whole city mobilises in response. Irileth answers the call, the city guard rushes out to defend the people, and even a newcomer who has been in Whiterun for all of four minutes steps up to fight. So, when the moment to protect the Whiterun finally arrives, does the mighty Sinmir leap to its defence as he should?
No.
He stays his ass inside the Bannered Mare in his FULL IRON ARMOUR and lets the real warriors get it done, then promptly returns to shitting on the security and pretending to be some hardened veteran.
He isn't just a fraud and a coward, but a useless fucking bum whose life serves zero purpose to Whiterun or Skyrim at large. Nazeem is annoying, but Sinmir is just a loser of the worst kind, and he deserves to be despised above and beyond anyone else in Whiterun.