First, I think disabling those routines is a temporary fix. When I ran Activity Monitor I saw that spinddump and tailspind were taking up a fair amount of CPU time, as measured by elapsed time run. I did the removal as documented below, but the machine still wasn’t running like I thought it should. Mail was crashing, safari took too long to load, and other things. So I set up a second time machine backup overnight, and with two backups on separate physical drives went ahead with a restart in Recovery Mode, did a disk reformat of the main drive, did a new install of the OS, then imported user files from one of the Time Machine backups. Now all is good. Even though Spindump and tailspind were reinstalled they don’t run anymore and things are running like they should. All that said, disabling spindump and tailspind so you can get functional enough to make a second Time machine backup and do a clean install may make a lot of sense for you.
The above are great answers. I'm adding this because people coming here who are running Catalina need some additional steps found online but with some effort.
With Catalina parts of the system have become readonly even for root, so a couple of extra steps are needed. The steps are to Disable SIP, remount /, killall Finder, turn off and rename spindump and tailspind, reenable SIP.
First, follow Dave Hamilton's great explanation of turning off SIP found in his great spindump/tailspind writeup, then substiture the following instead of his instructions on doing the plist modifications:
launchctl unload -w /System/Library/LaunchDaemons/com.apple.spindump.plist
launchctl unload -w /System/Library/LaunchDaemons/com.apple.tailspind.plist
mount -uw /
mv com.apple.spindump.plist com.apple.spindump.plist.bak
mv com.apple.tailspind.plist com.apple.tailspind.plist.bak
Go back to Dave Hamilton's description and enable SIP.
I already contacted Dave Hamilton, and he appreciated the note that he needs to update is nice writeup to deal with the change Catalina brought.
My mac went from unusable to near normal with these changes. I'm running a Mac mini (Late 2014) 2.6 GHz Dual-Core Intel Core i5 with 8 GB 1600 MHz DDR3. After the initial improvement there were still problems, so, as I explained above, I did a clean install first having two backups on separate physical drives. My conclusion is that if you are at the point of seeing tailspind and spindump running a lot you may need to consider doing a clean install of the OS.