I think they are actually now doing molded parts these days. You can only scale so large with a print farm. Very impressive setup and Prusa makes great printers and the owner seems like a standup dude. I just wish they could be more competitive in this market the X1C came out and changed things. I ended up selling my MK3S for it. I will gladly jump back to a Prusa if they have a printer for my needs again as it the brand that is my number 1 pick for a lot of reasons like being OpenSource and that something I deeply value
I think they are actually now doing molded parts these days.
They talked about that in the video. Some parts that are common across models and are no longer under active refinement are being injection molded (in house), but given the expense of getting tooling made, they choose carefully which parts they make that way.