There are so many unofficial escape sequences for rendering images in modern terminal emulators. Kitty has one, as does Terminology and iTerm (both different from each other). Then there is stuff like Sixel (supported by xterm), ReGIS (also supported by xterm but it's horrible to use) and other methods from VTs of old.

I really wish there was just one standard way to render images on the terminal (like there is one standard for rendering hyperlinks on the terminal), but there's an XKCD sketch somewhere about creating a standard to consolidate standards.