Slow disk/folder access from Explorer in Win 10 ver 2004 (but not in 1903); any known workarounds?

Question

Explorer entering a USB HDD folder with (approx.) 15,000 items takes 3-4 seconds with Win 10 ver 1903. The same folder takes literally 5 minutes with Win 10 ver 2004. (I have parallel Windows installations since MS forces us to be their beta testers.) In Win 10 ver 2004 Explorer "gets stuck" (but it's still actually trashing the disk) at this stage:

And there's continuous disk activity from explorer:

The main issue is that sorting items in that folder (by any criteria, I normally do it by date) is not possible while this is going on. So, is there any known workaround for this "improvement" in Win 10 ver 2004? It worked/works just fine in 1903...

The worst thing about it is that it restarts this whatever green-bar scan is doing for apparently no reason, even just resizing the Explorer window in 2004 seems to trigger it. Or even hiding and unhiding a window in front of Explorer, not even touching its own window:

The 2nd time it's doing it, I can't hear the disk trash anymore, which probably means it's doing it from RAM/cache, but it still takes on the order of minutes !! (Ok, maybe 30 seconds.) During which I see no disk activity, but that stuck green bar still prevents sorting of items... there's 100% CPU usage on one core while it's doing this (the 2nd and subsequent times), from Explorer. The gree-bar wait also gets repeated whenever you sort the items. (And simply scrolling up and down in the folder periodically re-triggers the green bar too.) And the "best" part is that if I leave the computer idle for an hour or so, apparently the stuff cached in RAM expires, so the mega-slow disk rigmarole starts again when accessing the folder. Also, saving any files (from the web browser--doesn't matter which) into that folder triggers the green bar again if Explorer is open on that folder...

The more weird thing is that only happens on the USB drive. I have an internal HDD as well, with a similar folder, 20,000 items. Instant access from Win 10 2004, no green bar triggers (or retriggers). Indexing is turned off for both drives.

How comes booting into 1903 manages the same the same activity 10-60 times faster, on the same disk/folder, with no green bar "retriggers"?

Answer 1

I think I've ameliorated the problem for now by changing the access pattern from "video" to "general items". (old setting below)

It's still slower in 2004 than accessing the non-USB HDD, but less awful, resorts don't seem to trigger the green bar anymore, although saves to the folder still do; those even happen on the internal HDD, but there the green bar takes under a second. On the USB HDD it now takes 5 seconds, instead of 30, so an improvement...

(suggestion found in a couple of places https://lifehacker.com/fix-an-unresponsive-windows-explorer-window-with-the-gr-1490366886 ; https://community.spiceworks.com/topic/454342-windows-explorer-green-ribbon-of-death)

Interestingly, in 1903 the setting for that folder is/was to optimize for "pictures". I guess 2004 decided to switch to "videos" all by itself.

In 1903 when you switch the optimization kind for the first time after a reboot it takes noticeably longer (green bar) than in 2004, maybe a full minute. But subsequent changes/saves/scrolls/re-sorts are basically instantaneous in 1903. I guess 1903 does some "full" reindexing of some kind the first time you hit the folder with a change in settings. But then, there's no green bar retrigger in 1903 do something to the (USB HDD) folder, no matter what the optimization choice or action. I've even tried "video" to see what happens and there's no green bar for saves (or scrolls or re-sorts) still. So there seem to have been some changes in 2004 to do some kind of "incremental" green bar thing... which actually is more painful in the long run.

With optimization set for "general items" 2004 is fairly reasonable: even after a reboot, entering the folder only triggers the green bar for 3-4 seconds, after which resorts or scrolls don't trigger it anymore. Interestingly, after a reboot (with "general settings") saves don't trigger the green bar either in 2004. So it seems unlike in 1903 a reboot is required in 2004 for optimization changes to fully take effect.

Still, rebooting into 1903 with "general items" on that folder results in no green bar whatsoever on first access, so 2004 is still a bit slower on the same settings and scenario...