Not sure about the criticism of Strava and motivations behind those who use it. I use it to track my rides, see how I did, analyze my heart rate data, cadence, things like that. And, as you said, it's somewhat of a social platform. And that's not a criticism, that's a good thing. There are several cyclists with whom I've now ridden a great many times, and one guy is a pretty good friend now, whom I met only because we saw each others' rides in Strava, made contact with each other through Strava, arranged to ride together, etc. Now that I know more people who ride near me I've made some contacts by talking with them, but almost everyone I met originally who rides around here I met through Strava. Just last week I finally rode with a guy I've "known" on Strava for quite some time (through mutual aquaintances/seeing people I knew ride with him, etc.). Some of the coolest rides I've done here in Arizona, like climbing Mt. Lemmon, were done with folks I had originally met through Strava, and would otherwise never have known.

I could just as easily say that Strava is for outgoing folks who wouldn't mind meeting other people to ride with, and use something else if you're a loner/hermit type who just wants to ride by yourself and never get to know or interact with anyone else.