GoT is about the victory of the historically downtrodden--women, eunuchs, slaves, "wildlings", bastards, and a dwarf--over the traditionally powerful men. GoT is full of sex and death. And, best of all, was totally unpredictable. (For the first six seasons, anyway)
LotR, on the other hand, is about the victory of a bunch of white males going to war against a multiracial army. Their goal: to help a white man from a "superior" race (the Numenoreans) reclaim his birthright: dominion over almost all of middle earth. The only two women in the books with any substantive role are Galadriel and Eowyn. Galadriel is in a no-win situation; most of her power is destroyed when the One Ring is destroyed. Meanwhile Eowyn, the scrappy shieldmaiden of Rohan, is rewarded for killing the Captain of the Nazgul by getting to assume a gender-normal role as the wife of the Steward of Gondor. (HT to David Brin for pointing a lot of this out first.)
Worst of all for the TV series, in LotR everyone already knows what's going to happen!