There are plenty non-web vector map renderers, but they generally provide a full GUI widget, not a simple "extent -> png" function. I don't think creating that would be too much work, though: Just set one of those libraries to render to a texture.

Maplibre Native even seems to have a headless "render to PNG" backend: https://github.com/maplibre/maplibre-native/tree/main/platfo...