Did you do a roll-out to measure the wheel circumference?

Just for kicks I tried wrapping a (fabric) tape around the tire, vs rolling out & it came out at least 1cm different.

I would get that dialed in, & then not worry about it. GPS does stuff like measure to the riverbed when you go over a bridge,

& Strava on a phone can include your trip into the bathroom- it's all an approximation.