Whether GIF was intended for this usecase or not (it wasn't, the GIF spec specifically calls it out as a bad idea [0]), it's overwhelmingly what it's used for in practice. Therefore anything that can displace GIF in this space is a replacement.

[0] https://www.w3.org/Graphics/GIF/spec-gif89a.txt

> Animation - The Graphics Interchange Format is not intended as a platform for animation, even though it can be done in a limited way.