I am from Munich but live in Hamburg. I have read all comments here and experienced people visiting and heckling Munich for decades now. People can talk a lot of shit about Munich, many things rightfully so.
But dirty? I have literally never heard anyone say that. If you think Munich is dirty you must be from Singapore or Japan and never visited any other city on the planet.
Münchner here. It is a very touristy city. Dirty? not so much in comparison to other german cities like Cologne or Berlin.
Uninviting and boring depends what you want to do. Nightlife in comparison to Berlin is poor. All the techno clubs are there. Octoberfest is a melting pot for the whole world. Americans and Australiens have a hard time digesting the amounts of beer.
