No supports 1-2 seasons ago, now several teams are running 3 support comps

I play Vanguard and Support mostly. I only get to play Dps every once in a while. Tanking has been awful this season and almost all my games I end up solo tanking. When I’m trying to figure out why nobody (including myself) can’t seem to get kills, I look at the scoreboard and see that the enemy team has 3 healers! I don’t get it. I don’t mind 3 dps as much anymore, but when it’s clearly not working for our team, they switch to a support instead of a tank! It’s even worse when the other team has 2 tanks. I can’t do anything some games!

And I still get games where someone locks in 5th dps, so I go 6th, cause I hate solo healing and then getting blamed for the loss.