I think hydration breaks can be defensible as long as they are a) conditionally triggered by pre-existing criteria that is b) created by an honest assessment of player welfare independent of economic considerations.
I can't say I think the halftime show is a big deal at all though.
Given how the world is heating up and weather is getting more extreme, I think there has to be space for player welfare. That doesn't mean there aren't options for how to implement these things, but I don't think adding 2x 3-minute hydration break (for instance) transforms football into some unrecognizable bastardized version of itself provided the impetus is health and safety vs. economics.
I can't say I think the halftime show is a big deal at all though.