I personally only use lattes as a convenient shorthand for ‘unaffordable repeated spending luxury’, whatever that might be.
This specific article focuses only on a $500-$1000 cushion and doesn’t just target lattes, it lists a bunch of stuff that people could consider. A small cut back on non-essentials over time could easily accomplish that for people who do have the ability to buy non-essentials.
Actually, if I were to be all judge-y, I would TOTALLY pick on crazy cable TV subscriptions as the worst. My neighbor re-amortized his mortgage over a longer period to lower the payments. He was complaining about his TV/cellphone costs. I commiserated in a general sort of way but then had to bite my tongue when he said it was around $600/month “because I just have to have all the channels”.
(Going just a bit further, it might not be a bad idea to have a couple of hundred bucks in cash in your house, in case of wallet loss or identity theft.)