Can’t watch youtube at work but I think the judge got this one right as far as I remember the two songs. the intro to stairway is recognisable but its still just a variant on Am–G/B–C
The arguments around copyright of songs is a big tricky subject, have a look at the Adam Neely videos for the spuriousness of claims nowadays. It’s getting to the point where lawyers are arguing about chord sequences and two note riffs which is just daft IMO.
Also there are a number of lawsuits being brought by legal teams on behalf of artists who have either deceased or have sold their rights which is pretty mental (Marvin Gaye vs Ed Sheeran is a prime example, the rights to Marvin’s songs have been bought by a venture capital fund who are looking for anything close to go and make money from) because copyright is designed to provide income for the creator before passing into fair use (and go and google Disney and fair use for how they’ve stretched the definition…)
There’s still a place for copyright but this isn’t helpful.
Maybe Led Zep should sue RHCP = the outro of Under The Bridge is a clear rip-off of the outro riff to Stairway ! 🙂