> I can't see how a font could have or lack a "feature"

Oh boy. Everything about a typeface is a feature, and many of them are functional and not just stylistic choices.

- Monospace glyphs are a feature almost everyone here is familiar with and appreciates.

- Serifs are a feature for readability

- Open apertures like in humanist fonts are more readable

- Closed apertures in grotesque fonts make the text more dense

- Stroke contrast

- X-height

- Variety of weights

- Ligatures

- Dotted or slashed zero to distinguish it from capital O

- Features to distinguish capital I and lowercase l glyphs

...these are all features of a typeface.

Not to mention all the far-out OpenType features.

https://en.wikipedia.org/wiki/List_of_typographic_features