Except the glitziness of retail/hospitality/public realm has always been used as evidence of gentrification, so it seems to me that it's reasonable to use it as evidence the other way when it gets scruffier.
I think it’s just one of the indicators, and high streets nationwide have been struggling since Covid. It’s interesting to think of how much of a mainstream anytown central Brixton continues to become. Chains like Chopstix, Pret, Itsu, Five Guys, etc have continued to set up shop here, generally replacing independents, while Morley’s and M&S have both made substantial investments in their stores post-Pandemic. There is a whole strip of new tenants in Market Row too following the recent refurb there.
I was thinking of this the other day when I was out in Peckham for the first time in a few years. Rye Lane still feels very run-down and deprived in the main. Beyond the Levels and the Bussey Building/Copeland Park, the newer spots are pretty thin on the ground - the odd few arches around the station and that godawful Market Place street food complex. Brixton town centre by comparison is smarter, cleaner, and looks increasingly more like Clapham High Street (physically at least).
The other thing about gentrification is the way it moves through phases and eventually results in long-term social change. The artists and independents have passed their peak, and the night-life might be a bit quieter due to that, but that’s in some part because corporates now see Brixton as a place they want to be, and they’re more risk-averse and less inclined to operate round the clock.
It’s been noticeable where I live how much things have continued to change these past few years. Everything from the resurfacing and paving of the streets to the continued renovation of houses, to the declining roll in our kids’ schools as the neighbourhood has gradually seen a population shift to higher income households with smaller families.
To me there’s no doubt that Brixton has become a smarter, wealthier place over the past couple of decades. Walking down Brixton Hill is an instructive example - every single building between St Matthew’s and Water Lane has been renovated or replaced in the past 20 years, and it won’t be long until that reaches all the way to the South Circular.