The Nissan Leaf uses larger cells [1], each roughly the size of a ream of printer paper. So there are real car designers who agree larger batteries are worth considering.

Of course, the Leaf makes a bunch of other decisions that are different to Tesla - lower price point, smaller battery/reduced range, air-cooling batteries instead of water-cooling, a (now abandoned) battery lease scheme, and suchlike.

[1] https://www.google.com/search?q=nissan+leaf+cell&tbm=isch