It's been getting better in the past decade but similarly, one of the papercuts of the Linux desktop experience that used to bug me was how you could kinda feel the numerous layers it was composed of slipping around a bit. I think all modern OSes suffer this to at least a small extent today.

That "tightness" you mention is quite tangible on my 500Mhz PowerBook G3 when it's booted into OS 9. It would be nice to get that back in its entirety somehow.