I suspect it's because the claims may be exaggerated and not really true after all.
That's possible, but it's also possible that the research you're talking about is averaging numbers over the entire US, while this solar plant is in a relatively southern location that gets bright sunlight almost all day every day all year round. There could be other differences, such as comparing fixed photovoltaics on mostly not optimally angled roofs (many of which have surfaces that don't get much sun) to this completely different system. It's not photovoltaic at all, and the mirrors are continually adjusted to maximize the amount of energy captured. It's clearly not an apples to apples comparison with putting solar panels on houses.
I remember reading an estimate from long ago that converting something like 10,000 square miles of Nevada desert into a solar power station could power the US. Presumably solar technology has improved since then.
I've never understood the reaction to fusion of "we shouldn't be pursuing fusion power because it doesn't work". Photovoltaics didn't work either until someone made them work. And the same with every other source of energy. I think the other commenter has pointed out one major reason why there's so much interest in fusion. The other is that if it can be powered by heavy water, we'll have an enormously abundant source of fuel.
As for the solar plant, ignoring transmission problems 5,000 square miles could power all the households in the US? That's a square 70 miles on a side. I think we could spare that much of Nevada.