I'm pretty anti social media. I use the under-armor app strictly because I sometimes have issues with the odometer on my cycling computer (the sensor moves and then it quits working until I stop and fix it) and the map feature is cool. They keep sending me emails asking if they have the right e-mail or something. I keep not responding.
Strava is of no interest to me....I prefer to ride alone for the most part so I don't need an app suggesting friends to me. I have some non social media pals that I can ride with if I want company. If people are into Strava that's great for them....if it helps them enjoy the experience or meet fellow riders ...go for it.
Personally I cringe a little when people post that stuff to other social media....a bit too much "look at me .......look at me !!!" I talk about my rides with people at work .....if I see their eyes glaze over and the look of abject boredom set in I stop. As it is I have gotten a few coworkers on new bikes.