The videos probably told the truth - so the problems were in the bass as you say, given that the voice was perfectly clear and the top end pretty close to Qobuz which I used as a reference. The upper bass was better with Dirac off, the lower bass... well, it's a phone video and I don't trust that.
I'd venture that some of those peaks at least were from the desk not the room, and some isolation would have helped, even ad hoc.
Once someone has completely lost trust in their speakers, though, it's hard to retrieve the situation without replacing them.
@AdamG247 is a Desktop Audio forum worth considering to get that expertise into one place? It probably wouldn't have helped here, but at least people asking about desktop systems would have somewhere to go and better people seeing it?