All will seem pretty standard, you go to a bar on a street with four other similar bars, then you realize that these four bars are the only places with people in them in the entire downtown area. You leave the bars and walk a block and you can hear your footsteps and thoughts echo off of the empty blocks. You might be lucky to see another soul on foot. There is just a lack of life in a lot of American urban cores, and that's not a feeling but a fact backed with population data. Cleveland in the 1950s had nearly 900k people living in the city. Today it's a bit over 350k people living in the city, a large portion of it is literally hollow (or demolished and converted to surface parking lots) due to large swaths of the population moving to new suburban developments in the 1950s, and a lack of immigration back into the urban core. The overall metro population of Cleveland has been pretty stable, if declining, but the city itself only appears as a city from 9am to 5pm, and during the odd sports game, as a result. Restaurants and stores might only be open for weekday lunch because there isn't foot traffic otherwise.
This isn't true in every city, however. For instance, Los Angeles experienced a similar white flight effect with the development of their surburban neighborhoods, however in the wake of this population shift, immigration continued to occur and the population continued to rise at double digit rates every decade. Now, the former neighborhood of the Los Angeles elite of the 1920s, Westlake, is a thriving community of central american immigrants and the densest part of the entire city. The same cannot be said about the Cleveland analog, millionaires row on Euclid Ave, which used to count Rockefeller and Carnegie among their storied residents.
See also: the hastily made Cleveland tourism video (parody): https://www.youtube.com/watch?v=ysmLA5TqbIY
[1] To explain what I mean by this, here in Germany it's very common to have smaller, say 8-12 unit apartment complexes that are not surrounded by a small sea of asphalt for parking; the parking is completely underground, so up front you have just maybe a small strip of greenery. And then they actually have a good-sized shared backyard, and the building itself doesn't look like it's trying its best to ape Soviet-era brutalist apartment blocks.