So which would be the more accurate?
Neither is more “accurate” they’re just gps tracks, the Calories and Wattages are estimates based on that plus whatever other data/information you’ve provided to Strava.
For example it takes account of the type of bike you tell it you are using, try editing your ride and telling it you used an MTB and then change it to a Road bike, I bet the estimated figures change significantly…
The fact that you basically did the same route at the same time matters not a jot to strava’s al-gore-rhythm, if you’ve told it you weigh 20kg more and you’re using a Fat bike, it will estimate your Calorie use / power output as being higher than your svelte buddy on a Road bike…
Crap in, Crap out is the old adage I believe.