I think there's both a legal defence (its for legitimate research) and a law-change-advocacy (we think copyright in these works is silly) component to what they're doing.

I don't think you are wrong about the risks to them in fighting the case with what looks to be such abundently clear IPR over the mechanical recording. But, I do think the wider fight about what "should" be the IPR here, is worth fighting.

That advocacy lies in the part of your comment which heads off the "RIAA is bad" fu.