@gdgipson
Gonna play the devils advocate now but sometimes (but definitely now always), the reason your random teammate pushes and just dies is because you didnt follow =)
Ive been in many situation when I single handedly knock one enemy and do 120 of 150 dmg on the second without loosing any HP myself. I then check the teammates HP on the HUD and see they are both full and I spam enemy here to indicate that I am going in to finish this easy 3 vs 1.2 fight. I go in, fight, perhaps knocks the one I already cracked and then dies to the last player but thinks to myself "no worries, my two full health teammates will 2v1 this guy easy" but realizes they ran the other way and now is half way up a jump tower and says "wHY dO yoU pUSh AnD dIE nOOOb???" =). There are so many playing styles and none of them is "objectively" the right one.
I usually ask "aggro or safe" at the beginning of the match, or try to assess based on their legend pick and the weapons they choose what kind of players they are. A Wraith and an Octane with shotgun and SMG will probably push everything whereas a Caustic and a Watson with a sniper will probably play more defensive =)
But then there are ofc those who just dont care. They rather fight, die and join another match if they dont win that fight. This also in ranked if they are smurfs.