I still think one of the craziest examples of multiplatform streaming being required is from Pokemon. They have a whole guide on how to watch every season:
It's more the result of there not being much demand for the entire 20 year run of Pokemon, so they didn't bother keeping them packaged together. Otherwise they'd have priced it accordingly, and the services may not have wanted it at that price.
It's like how classic Doctor Who and current Doctor Who weren't packaged together: the demand for one was diff than the other, so it made sense to let streaming services only pay for the one their customers wanted most.
A huge part of that is season 1 of FLCL is two decades and entire production companies apart. It's likely entirely down to a matter of how difficult it is to get rights for anime. Cartoon network was involved in the two new HD seasons, and is much easier to deal with that Gainax.
I've only seen the first season lol. Planning on starting the second tonight. Apparently there's a 4th and 5th season as well that I'm just learning about, so 2 and 3 must have gone well!