I do fear that linking Dropbox to Trezor is a sure shot way of leaking enough meta data that you hold crypto.
also the dropbox labels are literally stored in a folder /Apps/Trezor/, which would make it plain the account user owns a trezor hardware wallet.
I have held off labeling anything for now, but was considering a second dropbox account on an unlinked email address to make it less apparent. otoh it probably beats forgetting why i setup "account #1", "account #2", "account #3" etc. a few years down the line.