Even a lawsuit without merit would require lawyering up and suck scarce time and energy. Adobe has deep pockets and lawyers on staff. Darktable has volunteers.
I agree. I think never mentioning Lightroom is a way of steering clear of meritorious suits and reduces the likelihood of a frivolous one...since even a frivolous lawsuit could be fatal. Anyway, "here is our cool thing" is probably organizationally healthier than "us against evil corp."