I think instances where the end ISP is peered directly with Netflix and demands more money is not valid at all. That should be normal cost of doing business to increase capacity as the consumer demand grows.
The topic of interest is instances where the ISP is not directly peered with Netflix and uses upstream providers and those providers are trying to make content providers absorb the cost of increasing peering capacity for services that traverse their infrastructure.
One could make the argument that Tier1's should never be the choke point as they should be keeping up with the times and be proactively increasing capacity.
One could also note that it's 2021 and Cogent and Hurricane Electric are still not peered.