Also I think generally those become great Tolkien fans who get to know his works in their teenage years. At least the few whom I know personally they are all that.
For an adult it still can provide some escapism, but for example the LotR longwinded narration and monologues are bound to be boring. And the inconsistencies will be more apparent ofc, and some explanations will be harder to digest.
Maybe my friends are right, and the Silmarillion would actually be better to read, since it contains shorter, mythical stories.