> then real price gouging is... what, when you charge more than everyone else

Honestly, a myth. It’s aesthetically pleasing (outside perishable personal essentials, like staples in a crisis). But if you have less housing than the population, the problem is the lack of housing. Getting uppity about pricing while builders wait months to get permits issued is performative at best.

Gouging: When I have a significant control of the supply, and set prices up in a way that significant parts of the supply get wasted because my profits are maximized anyway.

So one can argue that some cartel-like algorithms are price gouging, but it's unlikely to be what a provider of a lone AirBnb unit will do, as for them, going empty is worth zero.