Ask a bunch of folks in indie ttrpgs about the explosion in the scene in the past decade, and you'll find one overwhelming reason for where the impetus behind it comes from:
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Coming out of the design hotbed of the Forge scene and spilling out onto twitter after the closure of Google+, Meguey and D Vincent Baker brought the sublime post-apocalyptic game of Apocalypse World to the masses, but more than that, they have empowered designers to adopt a framework and set of principles, PbtA, that have opened us up to an explosion of vibrant, imaginative games. Successor formats such as Forged in the Dark (FitD) have proliferated across genre spaces, cross-pollinating each other with fascinating game design concepts and continued innovations.
The legacy of PbtA is vibrant and ongoing--but we can do something now to help the pioneers of the space. The attached ttrpg book bundle (great price, great games!) supports Meguey Baker in her ongoing fight against cancer.
I encourage you to check it out, and if you're able, support a great cause!