One of them lost their economic engine. The other is undergoing a real estate adjustment.
And you'll find plenty of web/creative agencies plying their trade in the area, although that sector isn't quite as distinctive as in - say - Manchester.
It's all part of the standard gentrification cycle: - collapse -> bohemian -> artisanal -> gentrified -> investment grade -> collapse... but hurried along some.
The current property tax system that most cities use make little sense. It penalizes people for improving and updating the structures on their land. Cities should be encouraging property improvements.
"Adjusted for inflation, the average office tenant paid a peak price of $34.34 per square foot during the fourth quarter of 2000, 65.5 percent more than the current average rate of $20.76, according to Newmark Knight Frank data. It's almost as deeply pronounced for Class A space — which has the best amenities and finishes. Today's Class A rental rate is $24.36 per square foot, but in the third quarter of 2001, tenants paid inflation-adjusted rent of $38.12 per square foot, 56.5 percent more than now" [0].
[0]: https://www.crainsdetroit.com/article/20170730/news/635141/d...
And a NYTimes article similarly, "The Empty Storefronts of New York" https://archive.is/JnhDS
Basically rents are too high, so businesses won't rent because it won't be profitable. In 2018 when the NYT article was written, "about 20 percent of all retail space in Manhattan is currently vacant, compared with roughly 7 percent in 2016."
So maybe this is bimodal: you have "rich" areas like Manhattan and SF and Seattle, where rents stay high even with low occupancy (landlords sitting on empty properties and enjoying the free ride of increasing asset prices), and you have "poor" cities like Detroit, where no one wants it and you can't even give it away ("free" property still comes with liabilities like taxes and maintenance).
When I talk to people from demographics that are accused of being gentrifiers (young professionals), the overwhelming reasons they choose a neighborhood are to be near restaurants, bars, clubs, cafes, shops, work and friends. I don't think I've ever heard of anyone pay a premium to be near an art gallery, or live near artists' private studios.
There are some gentrified neighborhoods that were known for their artists. New York's Soho is an example. These days the place is full of overpriced fashion stores, both independent ones as well as global chains. I can see why the shops were attracted - for branding purposes it might help to be associated with those artists. But I wouldn't say that artists turned it into a particularly vibrant neighborhood, at least not more than other neighborhoods in Lower Manhattan.
Is it that it's about correlation, not causation? It seems reasonable that artists would be attracted to an area for the same reason as, say, independent coffee roasteries (both require cheap space). I suspect it's only really the latter that are attracting new residents though.
The conglomeration of all of these people tends to lead to events, club nights and new and interesting businesses. This makes the area more attractive, causing others to move in and thus kickstarts the gentrification process.