Big difference is that Michael Bay Michael Bays every film he makes with his Bayisms - the swooping camera shots around the heroes, the huge megalotitan explosions, fuck’em car chases etc. this worked pretty decently in some films but it became pretty formulaic in everything. FWIW I love plenty of his films, but with time it feels like he got very thin on story and just super thick spread on action gimmicks. Personally I don’t see him today as the same director who made The Island or The Rock, but I’ll add that I thought Ambulance was a bit of a step up from all the Transformers salad he’d been making. James Cameron is a bit more legendary for his visionary projects. Sure maybe they don’t always tick the best boxes for story or character, but they’re deeply immersive and usually he tries to push some enormous boundaries vs making ‘safe’ stuff.