You are right, large alliances rarely bully small alliances and crush them for fun these days because of their treaties and protectorate agreements. If the dynamic has changed its because the alliances that operated in that way are gone and the treaties are partially their fault. When your only options are to be a protectorate, sign a treaty or be crushed for sport what do you think will happen. I cant answer for older nations relationships with each other, however pretending to be good buddies apparently goes all the way back to the early days on Bob.