The entire reason why it made a splash was Amazon pumping stupid amounts of money into marketing it, trough Twitch especially, the moment the sponsored deals stopped people just stopped playing it. Goes to show that no matter how you polish or market it, a turd is still a turd :V
Amazon wants a foothold in games, right, you know something they could have done with all that money that wouldn't have sucked and just pour it down the drain would have been buying a stake in Telltale Games.
Amazon's deep pockets and their online platform would have been a good match for the episodic games model. They don't need an in-house games division as much as they need a stable of developers providing good content people actually want. And games companies such as Telltale come up as a bargain all the fucking time.
However the reason they're not doing this is that they're greedy and want to cut the middle-man out. The same thing happened with movie studios, there have been a number of attempts to make in-house games by various studios over the years, but they almost inevitably fall back into the licensing/outsourcing model after a few years and/or sell off their games division to someone else. This has included Universal, Paramount, Warner Bros (the most successful attempt), Disney, even Pixar tried to mint some games in the early days. So they all think they're going to set up a games division and it's going to be great, and almost all come to the conclusion "well actually this is fucked" and revert to licensing.
The real core problem is that if you develop an in-house game as the publisher/platform then you're on the hook for the entire thing. You get all the profits if it succeeds but you reap all the losses if it fails. If you license it out instead then the risks are spread out. For example, TV networks are smart enough to outsource the making of TV shows to third-parties with contracts that favor the studio. They realized this is actually a better deal than trying to make all the shows themselves and the risks from developing shows that fail are spread around: only pay for the show ideas that look good: if you in-house the entire process you're paying someone by the hour to come up with ideas for shows, and they're going to mostly be stinkers, because of Sturgeon's Law. Coming up with good ideas doesn't fit well with an hourly-paid-employee model.
The only reason movie studios think they can pull this off with games is that they underestimate how hard it is to make a good game, seeing it as a commodity item, like a branded lunch box or something. So they bring everything in-house to try and undercut the market and/or in-house the profits, but they miss the fact that they don't get the economies of scale anymore. Sure, Ubisoft and EA take a big chunk of the profits, but they also have expertise from developing literally hundreds of games and spreading the technology costs among those. You get all the profits if you make it yourself but you need to have all that infrastructure too, and you're pretty much reinventing the wheel to do so.