> part-time, dissertation-only PhD programs

It's just getting worse and worse. I believe you're trying to argue in good faith but maybe you should just stick to stuff you know about.

There is nothing about 'dissertation only' that makes these programs 'part time'. I'd argue that a good German or French university (I would guess the UK too, but I know less about that system) has more comprehensive and more stringent coursework to the MSc level than most US universities have for their PhD level. They don't do additional coursework because they're 'done'. Talk to those PhD students (and their advisors) about whether they consider that work 'part time'.