Is 16GB of storage enough to run HA?

Hi there,
why does HA need several GB as the image is less than 200 MB, see Install Home Assistant.
Here is said that the

In Hass.io Recommended Minimum config it is said

That is not little. I say that, as I’m about to get a new NAS what comes either with an M.2 NVMe interface or eMMC and building up GBs tend to be pricey. Any chance to move some data to the external 2.5" drives?