They’re not profitable for cities, they’re profitable for people who bought land in the area before the development of the stadium. Look into who is pushing for the “revitalization”. It’s usually property developers who just bought cheap land in the area.
They get subsidized improvement of their property, and can sell at a profit or make some minor “improvements” (paint and landscaping) and rent it for a lot of money. I’m not saying that developing these properties is bad, but cities usually don’t make back the money they spent on the stadium. They lose money and property developers gain (and donate to local politicians).
Cities should never give companies or developers lower taxes in exchange for “revitalization”. No developer will invest in a project unless it’s already profitable. If you don’t make them pay taxes, there’s no way to make it up in “jobs”. Companies that can be lured with tax breaks will leave as soon as they get a better deal somewhere else. It’s not sustainable.