I just finished watching The Defenders. It reminded me of a classic comic book crossover. Specifically, it reminded me of just how contrived comic book crossovers were and how they were mostly just excuses to see our heroes punching bad guys together in between punching each other.
You know that episode with the Defenders standing around in a large empty room yelling at each other? That was basically like half the scenes in Infinity Crusade. Plus Zero Hour had a lot of scenes where the good guys were standing around gaping at a computer screen, which we were at least spared in the show but instead got the exposition around dinner in a Chinese restaurant. Smaller crossovers seem to work better, at least when talking about the Arrow universe.
Anyway, I guess the punching in The Defenders was fun but otherwise we really need better narrative justifications for crossovers.