As to your first question, I would move to Chicago not for dating prospects but for other reasons...activities, parks, cultural opportunities, food, architecture, all that stuff. The increased dating pool would be another reason, but not the primary reason.

As to the second question, I don't think it's hard to explain. I know people who have done what you're talking about, especially post-COVID. But...couldn't you just move to an outer suburb of Chicago and reverse commute to the office? Possibly try to negotiate more WFH time after you've been at the company a little longer?

And for the third question, again I don't think it's hard to explain. But while you're AirBNB-ing, I would fully concentrate on exploring the city and figuring out whether you like it, and setting down some soul roots. The AirBNB situation isn't a red flag, but I would prefer to date a guy with some stability and not feel like I was the only thing he was attached to in the city.