I don’t know what a .webp file is but I don’t like it. They’re like a filthy prank version of the image/gif you’re looking for. They make you jump through all these hoops to find the original versions of the files that you can actually do anything with.
It’s lossless, it’s meant for 2D and drawn graphics. Can’t do that much with lossless compression.
It’s still bad compared to modern lossless algorithms. PNG is very old and even though PNG encoders have evolved, it is still fundamentally a decade behind modern lossless compression algorithms.
For example: JPEG XL in lossless mode compresses at least 30% better than PNG.
Also, PNG is not actually lossless in many cases. PNG only supports RGB colorspaces. If you try to store anything that’s not in an RGB colorspace (e.g. a frame of a video) in a PNG, you will lose some color information as colorspace conversion is not lossless. Example of someone running into this issue: https://stackoverflow.com/q/35399677
JPEG XL supports non-RGB colorspaces so you don’t have this problem.
Okay but that difference is not as critical as with jpg, which are also more abundant. The bigger problem with png is that people use it for things it’s not meant or designed for - frame of a video being case in point.
If anything, it just proves how lacking we are in other image formats, when we keep shoehorning clipart formats like png and gif into other duties. Well not lacking as in not having them, but not using them.