My favourite Windows 10 build is 17763 (Redstone 5), it has LTSC version, the old Hero Wallpaper and latest stable Windows 10 build in my opinion. I had many stability problems with 1904x, especially 0x801F0005 which means "An invalid name request was made." That error made 1904x series my least favourite builds of all.
Ehm... remoteFX? Edge, IE... A lot. But to put it simply, we can start talking about 2GB of wasted storage (excluding the user profile(s) )
LTSC 2021 has constant feature and quality updates. for example: windows backup being added after i think an August 2023 Cumulative update, search with the small taskbar size being added, an option in Windows Update to receive non-security updates early and for some reason, links about Windows 11 in Windows Update. as for Edge, it gets in the way. it's always pushed to the top of the file associations popup menu. i also don't want hundreds of megabytes taken up by what is basically spyware.