They got good bars and shyt there
Maybe the only good thing up there is the abundance of alcohol.

The quality of is subjective, unless you love American pisswater. I don't like going up there because it is otherwise dead if you're not a booze hound.
And, to be honest, you can get a better drinking experience in Chicago's Industrial Corridor in between Ashland and Damen near Lake St. There's an offensively large amount of breweries, and a lot provide indoor eating. And I say better because unlike MIL, it isn't crutched by Miller being nearby.
Downtown MIL is ... well, let's just say there is an area defined as such. It's REALLY small. You can forget you drove through it.
I like Juneau Park and the ped/bike path. Gorgeous little section of the city.
What is downtown Chicago? The Miracle Mile? That shyt is dead by 9pm
Mag Mile and Loop are corporate/bougie business centric, so of course chunks aren't open late. Who wants Burberry and random corporate offices open late nite?
There's plenty of extra things open late in the core, and when you start to get closer to the edge of downtown you find even more things open.