275GB "Other" files - will clean install and migration assistant get ride of this?

[mavots]

2018 Mac Mini 500GB running latest Big Sur with:

165GB of apps, system, files, etc
275 GB "Other" (!!!)
60GB available

I'm not sure when the giant "other" showed up exactly, maybe a couple of weeks.
I'm out of ideas of how to find and trash such a large amount "other". Lots of search engine research over the past few days.

I read somewhere about Time Machine snapshots. My last TM backup (on a Drobo) was on 2/19/22. In fact, I tried and could not mount the Drobo last night and run Time Machine. I only turn on and mount the Drobo to run TM every couple of weeks. TM is not set to run an automatic backup. The Drobo/TM not mounting may or may not be related, but it is coincidental.

***I'm considering a clean install of Big Sur and then migrating my existing CCC backup. My CCC backup drive is also really large so "other" is on that drive as well.
Will Migration Assistant ignore "other" or transfer it along with the legitimate files?

***How about a clean install of Monterey and then migrating my files to the new OS? Will Monterey migration assistant ignore the "other" files?
I'm planning on upgrading to Monterey in the next few weeks (v12.3) in order to be ready to migrate everything to a new Mac Studio next month.

Thanks for any help.

 

[mavots]

Thought I would follow up on this.

It WAS Time Machine snapshots, but more importantly, Carbon Copy Cloner snapshots. I deleted six CCC snapshots and over 180Gb of "other" went away. Deleting the TM snapshot got rid of 30GB more. Down to a manageable 80GB of "other".