I grew up in the Chicago area but moved to Arizona quite a few years ago. I hadn’t been back to Chicago in about a decade until taking a trip to our Chicago office in May 2022. The office is on the west side of the Loop, so I stayed in a hotel and went to several restaurants in the Loop area (Giordano’s at Jackson and Franklin — awesome — and Luke’s a block east on Jackson — sucked; I was fooled by Luke’s of Chicago, which is a really good place for Italian beef in Phoenix, but after visiting the Luke’s on Jackson, I don’t think there’s any association between the two.) I was in awe of how much nicer the Loop area is now compared to a decade ago. In case you don’t know this, “the Loop” is not a generic term for all of downtown, it’s specific to the area roughly bounded by Wabash on the east, Congress on the south, and the Chicago river on the west and north. It’s named after the CTA trains (the “L”) forming a loop in that area. It’s mainly a business district and used to be pretty desolate on evenings and weekends. It’s still not really a tourist destination (except for maybe the Sears Tower, now named Willis Tower), but it was much more active than it used to be. Even State Street used to be pretty dead outside of weekday afternoons, but seems a lot more active now. It was even cold and rainy when I was there, but it still wasn’t dead.
Despite that, Michigan Ave, although poorly named, is much more active than the Loop. It sounds like you know the area, so I won’t try to give you many suggestions, but will say that the Art Institute is one of my favorite destinations near the Loop. Also, I took the boat tour that departs immediately south of the Wrigley Building and it was great, despite the uncomfortable weather. I was blown away by how beautiful some of the newer buildings are, particularly along the branch of the river just off the lake.
Lastly, from the other threads, I can see some will agree and some will disagree, but my favorite Chicago pizza places are Giordano’s, Uno’s, Lou Malnati’s, and Gino’s East. I also like Portillo’s for Italian beef. I lived in the suburbs and, as I said, haven‘t lived in the area for a long time, so have no reason to argue against the opinions of those who live in the city now, but just wanted to offer my perspective. But the main takeaway I would want to give you is don’t believe the people who have never even been there but still want to tell you that Chicago and Gaza are comparable. You’d be foolish to hang out on the south or west sides (except around the United Center if the Bulls or Blackhawks are playing), but downtown, Wrigleyville, and other near-north neighborhoods are going to be fine.