None of that requires LFS; I compiled KDE via scripts many years ago. Why would LFS be needed for that? That makes no sense. Debian being slow is their problem, other distributions aren't snail-like like that. The default compiler used in LFS is also hardly a real cross-compiler, it is more a bare-minimum compiler for C/C++. This annoys me because e. g. I need fortran for R, so a bare-minimum compiler isn't as useful as a more feature-complete GCC. And GCC also causes some issues, e. g. like my problem with options.cc.
I think you missed the main argument though - LFS isn't quite as good as it could be. That is a correct statement that was made.
"Requires"/"needed".
LFS is about the muscle memory; the documentation; the cohesiveness.
I always recommend it to people and consider it foundational to my understanding of How Stuff Works.
Whether that amounts to a hill of beans in the AI world remains to be seen.
It is more how stuff is compiled than how stuff works.
Fundamental things like how processes are scheduled are not explained by LFS.
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