Yeah I was playing on Eichenwald yesterday and we did a shit job on offense. Only captured 3.5% of point A. So on defense I told the guys that we need to play on point at all time to prevent capture. We ran Rein, Winston, Mercy, Soldier, Symmetra, and Torb on the point.I don't think it's so much that people have to adjust tactics, but that the tactics they have to adjust to are shitty for the game.
You literally have to keep one person on the point at all times in that scenario, or someone can blink to the point and win it outright without ever fighting.
So the intricacies of a defense on 2CP are shot. Hanamura, for example, that has so many entry points but so many forced fights in chokes, either gets boiled down to a 6v5 or the fight only occurs on the point itself. It becomes a prolonged game of waiting for the attackers to stack their ults in either case.
Eventually we lost that when their Roadhog ulted and push us off the point but for a long while that strat work. They couldn't even get on the point. Whenever they come in we just wipe them, 3 people would chase to make sure they're staggered and 1 person would remain on point. It was a good strat.