A few moments googling confirms: Maury's Markowitz is up to his elbows in Solar Energy. Given his advocacy for solar, his head would explode if anyone talked about Solar with hyperbole and absolutely-nevers like he's done here.
Speaking as a degreed engineer and physicist, with childhood classmates, neighbors and professional colleagues now decades into their work in both next-gen fission and current fusion reactor design, I definitely get a bad vibe from all of Maury's hyperbole. They agree that fusion is challenging. But fusion isn't remotely analogous to vacuum tubes, nor is work and progress stalled. Maury's selling the impossibility of fusion, I doubt he's remotely qualified, and he's exaggerating to do so.
Nice Try, solar guy. IMHO, the worst kind of bad science is advocacy that overreaches your expertise, because it can smell true to other scientists. Next time, start with 'I'm __ with ____ (Solar), and here's why I've bet my career on solar:'