I think you are probably correct, although I fully enjoyed her in Hello Dolly. Felt she brought something unique to the role.
I am curious if there is a generation (or two) that doesn't have the Streisand performance embedded in their minds. I can't unhear Streisand singing those songs, but is that true of a 20 or 30 year old who hasn't seen the movie or seen it only once? Perhaps a new take on the role might connect with younger audiences.
I would imagine modern day perspectives on beauty, body image and other issues will be mined to update the revival. I'm not necessarily a fan of reinterpreting older shows through a modern lens, but it seems like it could be a draw here.