Watching the GCPerformance video, I feel terrible that he was called out to make this response. YouTubers bullying YouTubers is BS.
That said, I stand by my interpretation of the videos and Tavelo's response, which shows that management and process mistakes are being made at Tavelo.
However, in GC's video, one thing stood out to me: the idea that Shimano BBs fit fine, so he didn't bother measuring. Not only is this the reality for most people building bikes, but the cottage industry around "better engineered" bike parts is partly to blame for why PT couldn't fit his BB. Yes, the Tavelo frame is out of spec, but Shimano and SRAM use nylons to interface with the carbon as a wear surface and widen the tolerances to make a functional interference fit. Wheels Manufacturing also manages this by making the DS of their screw-together BBs slightly smaller. This is also a feature with BB bearings; Shimano and SRAM use plastic inserts with 24mm and 29mm spindles. In both cases, "better engineered" one-piece BBs and 24mm and 29mm custom bearings appeared to fix some issues. In situations where they aren't needed, they also create new problems. The trade-off for precision somewhere is also needing it on the corresponding surface. I am not defending Tavelo's being out of spec, but I am defending the non-engineers who say the bike works fine with their BB. It probably does for them because someone else engineered a part that deals with the potential BB being out of spec.
Also another vote for someone (aka, @patliean1) to buy and review the SC-R55D. With the standard round headset cap, UDH, and lower price, it sure would be interesting, though I suspect it will also likely need some attention on the seat post clamp.