I am averaging about 80ft of climbing per mile (15m per km) this year. I mainly do climbs, so my average might be higher than most. Most rides tend to be about 100ft of climbing per mile.

Strava is only as reliable as the data it is given and elevation is inconsistent. Many lower-end Android phones report far higher than average elevation. The same for dedicated GPS devices such as watches. Even Garmin devices report bad data.

iPhones tend to be correct as well as most modern and higher-end Android phones.