gifski

https://gif.ski/

Highest-quality GIF encoder

Gifski makes smooth GIF animations using advanced techniques that work around the GIF format's limitations.

Share your clips in their full quality, not a bland dithered mess.

Gifski lets you resize animations and tweak compression levels, so you can make your GIFs fit within upload file size limits.

It's more advanced than a simple color reduction.

I may want to test this tool out for ytgif