w3m displays images using w3mimgviewer by default, which is kind of a hack but works pretty well with xterm. It also supports both the kitty and sixel protocols;[a] I wouldn't call either of those a hack.

In fact I find it very strange how they're introducing the only terminal web browser with inline image support as one incapable of displaying inline images, then writing an entire paragraph about why you don't need inline images in the first place.

[a]: Only in the debian fork, mind you. The website seems to link to an unmantained version for some incomprehensible reason.