Found this that might be helpful. Seems like yes, with activity profiles.
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That looks like it could work! It's an older thread, and many people seem to be saying that the starting mileage can't be changed (from zero), but hopefully that's been fixed with updates since then.
Thank you.
It won't do it automatically, the Gear stuff is pretty weak and hasn't changed in years. All it allows is attaching gear to a type of activity, running vs biking, etc. After every ride you could edit the gear but I would never remember to do that.
This is classic Garmin software, 90% done and coded up by someone that doesn't use the device themselves. Being able to attach gear to profiles would make this feature great, as it is it is basically useless.
It won’t do it automatically
What would be a dealbreaker. Does Garmin expect people to do this manually, after every ride, with every piece of gear??