Btw, ‘Explosion of a Motor Car’, also by Hepworth, might be closer to now-familiar grindhouse cinema, and also had some special effects: https://archive.org/details/silent-explosion-of-a-motor-car

But yeah, about the OP film Wikipedia notes:

> As in other instances of the very earliest films, the film presents the audience with the images of a shocking experience, without further narrative exposition.

So indeed the genre seems to have proliferated right away.