I have 2 Gmail Accounts and neither show my Sent folders?

The folders must be set in gmail settings as visible to imap clients.

I don't find any bug reports of problems, unless you are using non-English installs or have added non-English language packs.

I think my Gmail accounts had too many emails and folders and trying to connect them to Thunderbird was never going to work given the variety of errors I was getting. If there was a way that I could easily say just connect the last 30 days of my inbox only I would have done that, but there is no easy way to do that.

You are making an assumption about "too many" emails or folders - this tends not to be a problem. But we'd need to see more information about the errors you were seeing.

Unfortunately the only posting where you cited an error also states you solved that problem "Unable to open the summary file for Sent on xxxx@gmail.com. Perhaps there was an error on disk, or the full path is too long."