Well, I think there's issue with slapping "accessible" versus "inaccessible" on a show as a universal label, especially with something that, though different, is still fairly mainstream. I still think the bottom line is that there are problems with everything, yes, but even stuff that's not typically "inaccessible," has its opposition; is Tarzan inaccessible? No. Does it work for everybody? Absolutely not.
The first time I saw Sweeney, I was very, very confused. There was too much going on, and I missed a lot of detail because I had a difficult time deciding what to focus on. That's Sondheim; the material itself to begin with, regardless of how it's produced, isn't for everybody. You have to be willing to concentrate.
A work of art is an invitation to love.