Those are fonts you can load with the vga driver. Anything recent will load with the drm driver (intel, amd) or framebuffer. This emulates a text mode (rasops) on a graphical surfaces (vga has dedicated text mode), and for that they use spleen.

https://cvsweb.openbsd.org/src/sys/dev/wsfont?sort=File

https://github.com/fcambus/spleen

And yes, it’s quite nice.