How do I sync tags between two Macs using Google Drive? I have two Macs, and I use Google Drive to sync my data. I created tags in Finder on one Mac for some of the files and directories in Drive, and they don't appear on the other one.

Is this possible? Or are tags restricted to the system they live on and not synced along with the files they apply to?

In case it matters, I don't use iCloud sync, and I'm not willing to turn it on.
The tags you see in the Finder that are associated with a file/folder are stored as extended attributes of that file/folder.

There is an excellent article which goes into some details about the portability/syncability of these extended attributes.  It suggests that Google Drive, amongst other cloud services, does not support the syncing of extended attributes, which is a pity. It lists three services which do support extended attributes, to varying extents, namely iCloud Drive (of course), Dropbox, and Resilio Sync.

I have personally found it effective when working with Google Drive to use workarounds to sync extended information. This includes different folder organization (e.g. red files in one folder, blue in other) or naming files differently. The exact way you'd do it is entirely based on the context of what you're trying to do, your goals, and whatever works for you.