Seems like merchandizing with posters, t-shirts, and action figures would be the quicker, easier, least risky way to do this.

Video games (which compete both in IP _and_ gameplay) seems like a much riskier proposition, relatively speaking.

It's deceptively tricky to build out this kind of strategy. IP builds product awareness, but it doesn't lead to a sustained gaming audience, which needs something more akin to a platform strategy per franchise(a Madden, Mario, Guitar Hero, GTA, etc.) - you don't want to just make a "Stranger Things" game, because even if it's a deeply realized experience, it doesn't loop into another franchise in the way that, say, playing a Queen song on Guitar Hero will lead you towards seeking out the game's recommendation for other songs; neither will it have the kind of premise that is as self-contained and enabling for player projection as a GTA.

Netflix has become known for optimizing content against the algorithm's feedback and not really letting a show run to a natural conclusion before killing it. This is going to be troublesome if applied directly to gaming, since it won't create platform reinvestment.

Until I see more announcements I'm going to guess that this will turn out like Amazon Game Studio - lots of investment without results.

That isn't an automatic indication of them having any real success. See Instagram's attempts to become Tick Tock. Their failures would be pathetic if I mourned their decline.