Why did Trump gain fewer raw votes in urban counties than Harris lost to Biden?

[DrScholl]

Examples

Cook County, IL:
Harris -333,479
Trump +16,945

Harris County, TX:
Harris -115,823
Trump +19,416

The Bronx, NY:
Harris -110,989
Trump +23,802

If you assume that all that Trump gained was swing from Biden voters (it likely wasn't) you still have a considerable amount of decline in Democratic vote in comparison to previous presidential cycles. There are a lot of victory laps that Trump broke through in urban areas but in reality the actual gains were minimal and I think that should be acknowledge before pushing realignment theories. Why didn't Trump gain more raw votes in these areas?

[Skill and Chance]

For the Northern/West Coast megacities, I would suggest it's just post-COVID population decline.  IDK how to explain lower turnout in Houston though LOL.

[GAinDC]

A lot of Dems just didn’t turn out

[有爭議嘅領土 of The Figgis Agency]

For the Northern/West Coast megacities, I would suggest it's just post-COVID population decline.  IDK how to explain lower turnout in Houston though LOL.

The magnitude of the dropoff exceeded post-2020 population decline almost everywhere.

A lot of Dems just didn’t turn out