I'm not sure how long you've been around $2nl, but assuming it plays similarly to $4nl on merge (the lowest limit), people will do crazy shit and you can't discount the spazz factor.
Villain is all in on the flop, correct? Stack-to-pot ratio (SPR) isn't really that relevant here. If you'd like, PM me and I can point you to some resources that may help you with SPR and when it's relevant (can't be arsed to look up specific pages right this second).
I think you are mixing up pot odds
with SPR. The pot odds
determine whether we are getting the proper odds to call against an all-in raise. The pot was 70c before the shove and the villain shoves $1.30. So we must call $1.30 for a chance to win $2. Our pot odds are therefore 2:1.3 or about 1.5:1, which means to break even we must win more often than 1/(1+1.5) = 40%.
The SPR has more to do with post flop play and how we want to play certain types of hands. Small SPR usually means we should be willing to get all in with weaker holdings, while bigger SPR means that we must play more carefully and should be more inclined to fold to big bets as they usually indicate more strength than big bets into small SPR pots.
Again, PM me if you want more on SPR. It seems like you might be watching training videos that are a bit above the level you are playing at, which is fine, but I'd suggest you try to pace yourself and pick up each concept fully before jumping onto the next one.