Hmm,
I'd imagined all game saves and other system files go to the switch console and micro sd card.
Maybe an external hard drive acts as a backup only and you can't run games directly from it but to actually prevent their use seems unlikely.
I personally don't think it conflicts with the Switch concept at all and if Nintendo prevent backups so people literally run out of space and can't move games to and from an external hard drive I think that will be massively inconvenient. However saying that I guess 32GB plus 128GB gives you 160GB and Switch games will be much smaller than PS4 and xbone full games.
I'll still hope for a decent feature built in that enables movement of games from different storage devices and guess there will be one going between system memory and micro sd so adding a usb stick or external hard drive to that function is not a huge difference. Nintendo will want to sell downloaded games in preference to cartridges because of higher profit.
