I found them extremely accessible, and I was a high-school dropout. (Admittedly a very late dropout, but a dropout nonetheless.) That was back when volume 4 didn't even exist as listicles yet. And, let's face it, the sheer size (and cost) of the thing, even then, was a bit intimidating, but there's nothing in it that can't be followed with a bit of algebra and the barest hint of what the kids these days call "pre-calculus". While it may be a bit of a slog to listen to Knuth, his writing is about as clear as it ever gets, things are laid out in a clear progression, and nothing jumps out at you suddenly without a clear buildup and foundation.

Concrete Mathematics, which isn't the easiest but also not the hardest math textbook, developed out of a course teaching the math from Chapter 1 of TAOCP. For people who find the first chapter, in particular, intimidating because of the math portions, it may be a good option to study before resuming TAOCP rather than just dropping TAOCP.

+1 for Concrete Mathematics. Learning more about discrete math had an immediate impact on my job as a data scientist.

And he is a funny writer. I didnt do the homeworks but found it surprisingly accessible

IronicaLly, I put off reading Seminumerical Algorothms for years because didnt understand it was numerical algorithms for computers without reals. The random number chapter alone is so awesome.

Oh, that's what it is? Ahh!!