2021-03-05:
Due to the slowness of BR 11, I use BR 9.1. Today I tried BR 11.0.1.109 again, as some CS updates and system updates (MacOs 10.15.7) have now taken place.

To my surprise, all folders now load quickly. The only exception: the desktop. Without further ado I cleared the desktop and then gradually brought all the elements back. The extreme sluggishness of scanning the desktop is caused by aliases on the desktop pointing to folders on the network whose devices are offline.

Therefore, BR 11.x should be changed in such a way that alias elements are ignored in the simplest case during the folder scan.

I believe Bridge is now slower that Phocus ... and that's saying something!
Definately a rentering / resource issue going on here.
HIGH SIERRA 10.13.6 2.4 INTEL 16GB

Today (June, 17. 2020) I installed Bridge 10.1.0.163 under Catalina 10.15.5.
The issue (see threads below) is the same as in 10.*-versions before.
Then I saw the hint here in this thread "removing favorites".
After I removed all favorites, navigation is fast as expected, while navigating through folders panel.
After defining some favorites again, switching between folders is at the first call slow again but then fast. I hope, that is the solution. I'll see.

For me a solution was to remove favourites.

In my experience having favorites folders causes Bridge to become super-slow, become milky and load for about a minute, before finally resolving *very* often whenever I navigate.

Removing specific favorites may solve the issue, *especially* when those folders are on network drives.

Today I had to switch back to Bridge 2019.
Bridge 2020 now frezes from time to time or runs unusable slow more and more. Could there be a problem with a cache or a database? I don't know. - Here in this board are some more similar threads. Please have a look! And please find a solution!

After some Weeks working with Bridge 2020, it slows down again. The workauround dont helps any more. If it go so on, I have to reinstall Bridge 2019, if possible.

Work around:
After a clean install of Catalina Adobe Bridge 2020 works fine.
I migrated all data manually! Preferences I have not migrated.

Bridge 2020 is slow here to under Mojave an Catalina. It is unsusable to use. It seems, scanning or caching a folder takes a lot of time. This not occours in Bridge 2019.