Not sure why NA is being singled out here. Bottles are largely the same shape (with a few functional differences, see below) no matter where they come from.

The round shape is mostly a historical artifact from early designs that were hand-blown. A hexagonal (bestagons!) shape would pack better in an infinitely large container, but since most shipping crates are rectangular, there will be wasted space either way, and round is far easier and cheaper to mass-produce. Also, as a carbonated beverage, sharper corners could create stress points and exploding bottles.

Toppling over could potentially be reduced with a wider base, but fitting in the hand is a hugely important factor for any drinking container. There are larger-based bottles, but they also need more specialized packaging and storage space. By using bottles that are similar size to aluminum cans, lots of infrastructure can be dual-purpose (I’m thinking of things like can/bottle storage in your refrigerator, for example).

Double the volume of what? Glass bottles have to be thicker than other materials, so to get the same volume as a can with the same size base, it has to be taller.

If you want to do a lot more reading, here’s a few sources I borrowed from:

https://sha.org/bottle/beer.htm

Regarding the functional design features referenced above:

https://www.hillebrandgori.com/media/publication/beer-bottle-sizes-and-their-surprising-history

Those ‘shoulders’ we keep mentioning remain in modern beer bottle design mainly for aesthetic reasons. Their original function was to provide a handy place for the yeast residue and dregs to collect, so that these didn’t pour out into the glass with the beer. Nowadays, most beer is filtered, so this design feature is no longer needed. Unless you’re bottling a yeast beer like a Belgian beer, of course.