It's a mobile friendly UI, that's one way this website stands out above many others.
Sure, it looks like the underlying process is a perspective shift, a gradient, and a blur, but making the UI usable deserves some credit.
If you don't feel like paying, you can repeat the process in any free image editor for a fraction of the cost.
Perhaps the value add will be bigger if the service gets expanded, for example when it also works with videos and allows for transitions. You can throw together a product demo video a lot quicker by combining that with some captions. It won't be much, but in many areas, it may just be enough to stand out in the crowd.
If I needed one of those "camera panning across a rotated screenshot" videos for a product, I wouldn't know where to begin. Maybe automate imagemagick? Teach myself Blender? I imagine for many tech illiterates (and there are a lot of those, especially these days) will have the same problem with plain images.
That's cheap if you're a media company or online marketeer that uses it regularly. The alternative would be paying for Photoshop and acquiring those skills.
Not eveything has to be free, and people are willing to pay for things. You just need to know the audience.
I think one issue I have with comment sections is that a lot of people only speak from their personal point of view, and don't consider e.g. companies or other individuals.
