ZOD says it's “digital files of modular 3D-printable terrain for tabletop miniature gaming”. These are the tiles, not the miniatures on the tiles, just in case that's not clear.
That said, they're cool tiles.
When ZOD is talking about tabletop miniature gaming, it doesn't seem to be talking about board games. It's talking about tabletop role-playing games, like Dungeons & Dragons which you might have heard of. There's thousands of those (RPGGeek catalogues over 8,000). Many of those do not use minis or tiles, some will. Dungeons & Dragons is one of the ones that does. RPG Stack Exchange has an intro to roleplaying and an intro to D&D available.
The Ill Gotten Games Patreon includes minis and even some creature designs for use in D&D, and lots of their posts have "dungeons & dragons" for a tag, so I'm reasonably confident that's the market they're targeting. It's also a market that predominantly wants stuff like this.
Tabletop Wargaming was also something they could've been referring to, but wargame players are not usually looking for tilesets the way D&D players are.