I know very closely an ex-pro, national level. He kept a decent road bicycle: alu, 105... no frills. He also did some trips in gravel and paths on a heavy MTB. His last outing was a 800 km trip on a rented bicycle.
As for the Strava rant going on here's my two cents. If somebody finds motivation or pleasure in completing segments and racing his Strava friends, be it a pro, an ex-pro or a sunday cyclist, let it be. Personally, I think ex-pros in Strava is a great thing: I suppose many people would be motivated to go out there and go around the same segments, joining them in rides... eventually dragging more people to cycling. I think this can only be good for the sport!