Lightroom Desktop: Syncing stuck forever

Not a single response for one of the CC reps? This is ridiculous and such a bad support...
So, I am paying just to report bugs and to pray for them to be solved? I am using Lightroom CC for 2 months and reported / found at least 4 bugs and the solution was always a workaround and "live with it"

February 2019, this problem still exists over a year later for many of us. 

I have tried (and cancelled) "Adobe Lightroom CC with 1TB" subscriptions several times over the last 4 months now within 14 day return period because the product still cannot accomplish Cloud Sync. I have completely re-installed and out of 27k pictures, 6 pictures remain in "syncing status". I have tried everything proposed in this thread several times - and Lightroom itself does not show any actual pictures in sync (when filtering). 

Adobe, for us entrust your cloud service to take care of our precious pictures, please show that you take this issue seriously and find out a way to fix the problem for us. As per (1) actually fixing the problem or (2) improving the in-built trouble-shooting issue that when the program says "syncing" we can actually see what it is "syncing". You had a year already.

I am also having this problem with Lightroom CC (for Windows 10) perpetually showing that it is "Syncing 1 photo" (see screenshot below).

It seems that all my photos are synced, however. When I filter to show "Syncing" photos, no photos appear (see screenshot below). All my photos are in albums, and all my albums have the blue icon indicating that all photos in them are "Synced and stored locally." All my devices with Lightroom installed (including on the web) show the same number of total images.

I checked my diagnostic log. Under "Sync/Error Assets" an asset ID is listed. I found that asset ID in Managed Catalog.mcat and noted the associated filename. A photo with that filename no longer exists in Lightroom CC or my local backup drive. I had permanently deleted that file (i.e., I deleted the file and then also permanently deleted it from "Deleted Items"). When I tried to re-import an image with that same filename (just for testing purposes), Lightroom CC warned me about the duplicate image.

It seems that there might be a catalog database entry, but no image file to sync, hence the perpetual syncing. Does anyone know a way to remedy this situation (without taking unnecessarily drastic measures)? Thank you!

Steps I have taken unsuccessfully, thus far: Restart the program, restart my computer, pause/resume syncing, uninstall/reinstall Lightroom CC, install the prior version (2.3). Someone on a support chat suggested that I delete the local Managed Catalog files and let everything re-sync down from the web, but I do not want to do that if I don't have to (that solution seems unnecessarily drastic for such a minor glitch).

Two weeks ago I thought I give Lightroom CC another try. I migrated a slice of my Classic Catalogue to CC. On the first day, everything looked good. But since I started working on my other devices (iPad and iPhone) too, I am also experiencing the sync issues again and again on Lightroom CC (latest) Desktop on MacOs (10.14 and 10.15).

First it was only a handful of pictures which I could fix by deleting and re-adding. But to be honest, this is still a pretty painful workaround. Now, Lightroom is stuck with 49 open syncs (see screenshots). However, the grid with the sync filter applied shows 42 pictures. Removing and re-adding is not feasible anymore. The pictures are spread across the catalogue.

It seems to be connected to my changes to the people view. While my mobile devices seem to be in sync, the desktop app shows a different state of my people assignments. Also, the picture that are still being synced seem to be the last ones that were touched by my people assignments.
I am not sure anymore but I think the diagnostic log was showing that only metadata is being synced.

I hope you can help. Already during my first tests I got the impression that the sync is too buggy to consider it production-ready. About 1 1/2 years later it is still the same :(
Even though Lightroom CC still lacks a couple important (geo-)tagging features, I really like the possibility to only take my iPad for travels and stil being able to sync and backup my photos. The mobile app is good enough to make some rudimentary adjustments and quickly rate and reject pictures. 

stuck on paste setting. i go to paste my setting to 10+ pictures and freezes