Can someone please explain to me what's so great about "Mandy"? SPOILERS!

Last night I watched "Mandy" with Nicolas Cage after hearing nothing but constant praise for it since it came out. Having finally seen it I'm dumbfounded that anyone could in good conscience give it a good review. It is by far the most excruciatingly boring movie I've ever seen. I understand that emphasis is put on the aesthetic elements of the movie and yes, it’s a very pretty film and the score is good, but there's literally no substance underneath it. It feels like it's being weird for the sake of weirdness, not because it's trying to say anything, and the whole movie is so SLOW. Everyone speaks as if they're taking 5 seconds to formulate their thoughts between every word and it feels like the whole movie is filmed in slow motion. Even the second half of the movie when Nicolas Cage goes on his "rampage" fighting the discount Cenobites and having the chainsaw swordfight is extremely dull (I never thought I would say that) and plodding. I'm all for slow burn films where everything is deliberately paced (films like "A Girl Walks Home Alone at Night", "mother!", and "The Lighthouse" come to mind) but everything in this films feels pointless and extremely pretentious. Maybe it's me. Maybe I just don't "get it", but I can't imagine what anyone could possibly see to love (or even enjoy) about this movie.

Also, why on earth would they set up all the rock music references and then not use a single rock song in the entire movie?

TL;DR: I thought Mandy was boring as hell, why is it so well-regarded?