Slow Time Machine user interface - only resolution to reboot?

I frequently have trouble with getting Time Machine to respond when I attach an external drive that I use a secondary back up (primary is our old Time Capsule). The symptom is that System Prefeneces > Time Machine takes a long time to respond to commands (e.g. two finger click on one of the assigned drives), and in some cases simply never responds.

The only fix I have found, and thank heavens it works, is to reboot the laptop. I can then immediately open up System Preference > Time Machine, and it seems to respond as I would expect, immediately.

This may not be a bug. Time Machine does seem to have self-throttling built-in:

https://support.apple.com/guide/mac-help/if-time-machine-is-slow-mh15140/mac

What may be going on is perhaps that I am simply trying to switch drives at a time when Time Machine has already decided to deprioritize operations. By rebooting, I might be simply resetting the priorities. Let me acknowledge that Linc Davis (https://discussions.apple.com/profile/Linc+Davis/participation) has provided the advice to reboot on other threads regarding Time Machine problems.

In any case - the situation is that Time Machine does work as regarding reliably backing up the laptop, but the user interface frequently becomes unresponsive until I reboot the machine. Does someone have another suggestion for a resolution? And if not - well, be advised that rebooting is worth a shot.