Generally, there are no differences, but I do not understand why you want to install both the old version/versions.
I'm talking about the 100% hard disk usage on newer Windows 10 versions. If I'm not wrong early builds had much better performance on a hard drive. Is 1607 usable on a hard drive or should I install Windows 8.1?
That's comparing apples and oranges. I ran 2016 LTSB on an ancient laptop with a 2.5" 5400rpm hdd just fine for years.
same here. my relative's old Dell Inspiron 580 desktop PC using a 1Tb Seagate SATA3 HDD is currently running Win10 LTSB 2016 (w/ recent CU) with no serious issues with the HDD (AHCI enabled in the Dell BIOS)
The only reason for having a storage drive pegged at 100% usage I can think of if there's something wrong with the drive itself. I've had the (dis)pleasure of seeing v20H1 Pro on a mechanical drive - it's not great, but there's no 100% usage "bug". Or maybe you have misbehaving software. Maybe even a virus. Those are, still, not windows bugs.
You should still explain what this statement means. I personally hear such a thing for the first time. And if you want, I now have all the computers exclusively on SSD and / or NVMe and have no problems even with the laptop released in 2006, which currently has the latest version of Windows 11 and the second disk has 19044.1288 (also the latest version). No problems. So I personally cannot imagine the problem you are talking about. Or maybe you mean this space reserved by Windows, the size of 6GB or 7GB, does not remember exactly.
I'm talking about the oh so great 5400rpm drive laptop's which as I know they're slow af on Windows 10 . Just tried it now LTSB runs just fine but Windows 8.1 seems much more usable