Yes, it's still worth a read, the assembly parts have become somewhat historic but it's a nice explanation of the "way of thinking" that's still valid today if you need to optimise in assembly (of course, targeting it for the modern archs).

Apart from that it's a nice read and some of the outdated parts might be skipped.

He actually made the point right in the book that the code was obsolete from a use perspective. The relevance (even today) was in understanding how the computer works so you could make tradeoffs. I still remember the video 7 story at the beginning of one of the chapters.

Those are lessons that are still relevant today.