More people are killed by doctors than guns yet that doesn't make the news.
I think you're putting way too much stock in "what makes the news".
Your comparisons don't really make sense anyway. We don't decide how to deal with something based purely on how dangerous it is, but also on how beneficial it is. If we could easily get by without ladders and there were thousands of people falling to their deaths from ladders, you could make a strong case for banning ladders. As it is, there are a lot of jobs we need ladders for, so there are warning stickers, OSHA training, etc. to try to keep people safe, and then we accept that accidents happen.
The debate about guns is whether we need them, or whether they're beneficial enough to outweigh their harm. And of course in this country the 2nd Amendment has to be taken into consideration as well.
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.