Expanding my comments into an answer for posterity:
Personally, I see no issues with asking questions about Bandersnatch here. Bandersnatch is an interactive story-driven adventure in a similar vein to a "Choose your own adventure" story. It shares elements with those "interactive CD" full-motion-video games of the mid-90s, or as a more modern equivalent, to Telltale games like The Walking Dead, Minecraft: Story Mode, or Back to the Future.
In terms of the medium, that hardly matters. We've fielded questions about Google Logo Doodles, Google Maps, (Twice!), and even Browser Error Screens, because of the mini-games these mediums contained, 'Netflix' is just another medium with the capacity to deliver gameplay. Bandersnatch features multiple different paths, choices to make, and different endings depending on those choices. It can be replayed too, making different decisions will produce a different experience and ultimately a different outcome/ending.
So yes, I think it should be fine to ask questions about Bandersnatch here. Do note that Movies & TV deemed it on-topic for them too, so depending on your question and the sort of answer you seek, you might consider asking it there.