I just counted (html > spreadsheet > row count / 2) the number of labels I have in my primary* Gmail account: it came to over 80.
How many do I use on a regular (daily) basis? 0.
How many do I use on a weekly basis? Maybe a handful. 5-10.
I do special purpose creates for them, but more realistically it’s easier to throw an IMAP setup on Thunderbird and use ImportExport Tools to do any significant manipulation of email data.
So, yup, it’s pretty much time for them to go… even though they were the hit controversial thing, with Gmail pulling us away from “real” IMAP folders at the time.
*Gmail: You can’t have just one. At least no self-respecting geek can, anyway.