Windows doesn't feel slow because the kernel or the filesystem is inherently "that" slow, it feels like a sloth overdosing on heroin because nobody at Microsoft gives the slightest crap about making it even a tiny bit faster.
It's staggering how the instant you double-click a file in File Pilot you're... back in the tar pit. (The Windows image preview app just spins... and spins... while it does God-knows-what with my CPUs.)
The contrast of going from one to the other makes the quality difference glaringly obvious.