Cable really is falling apart in the US. Sport was always a draw for having cable. I thought it would be this way for a few years more but things seems to be accelerating quicker. I don't understand why companies don't air sports on cable/streaming simultaneously like here in the UK with Sky Sports/Now TV?
Because the structure of the market is very different in the US.
Here, when streaming began to take off, the dominant pay TV distribution platform was the same company as the dominant sports, movies, and premium drama rights holder. They launched Sky Go before Netflix took off, so subscribers got used to being able to watch at home and on mobile devices.
Then they realised there was an untapped market of people who didn't want to commit to a 12 for 18 month contract. So Now TV is launched, carefully designed to satisfy a lot of people, but to miss the most premium quality / features that would make others pay for the full Sky package.
BT come along and see that streaming is taking off, so develop a very good app and allow people to subscribe to that directly, as well as having linear broadcasts. They might own a smaller distribution platform, but they could offer access via the dominant platform, and made sure they weren't missing from the second one in the market.
So as Amazon and Netflix have grown, although they've taken some rights from the existing players, at least those existing players are usually on the same platforms people are using to access the competition. That makes it much easier to compete.
Compare to the US, where there are multiple distribution platforms across the country and multiple content owners, each with their own vested interests. Disputes between them about terms and fees are very common. We have seen that here, but nowhere near as often, and usually resolved very quickly. Recently in the US, Comcast the cable operator was in dispute with Comcast the channel owner, so had to work Comcast customers that they might lose access to Comcast owned channels.
In the US the cable companies in particular stuck their heads in the sand and refused to accept the growing impact of streaming. Problem is, if they aren't content owners, what's in it for them? Why would they allow channels to broadcast on their platform if they're also selling directly to customers in competition with them? They (generally) didn't invest in their hardware and platform the way Sky did, so they haven't got that as a reason to stay.
If you are a cable subscriber you can now stream via most of the apps from the content owners, but that has taken years of individual agreements. And there are still issues - it's quite common that you can't stream the major broadcast networks live via their own apps, because they affiliate owners won't agree to let you, partly because of the money they make from cable retransmission fees. (Yes, the cable companies have to pay the free to air broadcast networks to have their channels on their platforms.)
HBO deciding it would sell directly to consumers was a big change, even that ended up in a mess around branding of two very similar apps and, if you were already a subscriber via cable, which you could access.
The one that really would change things is - most probably when rather than if - ESPN go direct to consumers. It certainly seems more likely given the direction Disney as a whole has been going. ESPN charges the highest per subscriber fees of any 'basic' cable channel in the US.