That's interesting indeed. But meh.
The difference in cost between 100 and 200 amp service is the feed from the power company's termination to the panel, and the difference between appropriate (where 200A does not cost nearly twice as much). We're talking small hundreds of dollars of difference here on any normal home, maybe a little more if the lines are buried. It shouldn't really be a factor either when building a new home, or refitting an old one: This is a very small budget item, down in "no-brainer" territory. They say it might be 30%, and they might be right, but the numbers are small compared to everything else that goes along with it.
200A FTW. It's enough for any normal-to-large American household, including the hot tub and the pool. 400A? Now we get into serious disconnect switches, multiple panels by default, and etc (which gets expensive!).
Srsly: I ran the same aforementioned ancient house (with all amenities including the dishwasher -- literally everything aside from the electric clothes drier) on a portable 6500W generator for two weeks following the Derecho a few years ago. Most of the lights were CFL, but the chandeliers weren't (by choice) and we burned the hell out of all of it. Multiple fridges, a deep freeze, etc.
It didn't ever really break a sweat, generally, even when it was over 100F for days at a time, all of the window air conditioners were cranked up, and we decided to have Movie Night with the BFT and the multi-kiloWatt audio system. I totally expected to be chasing popped breakers, overloaded cables, and had several fire extinguishers handy, but the 2x30A (ie, 30A @ 240V) from that portable genset was apparently enough*. (Sure, it would bog for an instant now and then when a compressor-load started up, but it recovered quickly and nothing that it was powering ever gave a shit.)
(As an aside: The neighbors hated us, but that wasn't anything new even though they were in the dark and we had a noisy generator. We also gave them all free wireless Internet for the duration, which was amazingly easy when the airwaves cleared during that long power outage, and many of them took advantage of that according to my logs.
We also tried hard to offer to let anyone nearby charge phones/whatever and run a fridge/whatever if they had enough extension cord to reach, but there weren't any takers, so fuck 'em.)
*: It wasn't at all cheap to fuel it, and it wasn't easy to find fuel, and it needed oil changes every 30 hours according to the manual, which I generally performed on-time. It also didn't seem to make anywhere near as much difference in fuel consumption as I expected between lightly-loaded and ridiculously-loaded, which is what led to the consumption-spree outlined above. But that's yet another topic.
**: And I still don't know what the 400A households are all about, except perhaps for them being sold a bill of goods. Nothing they have going on, even all-at-once, requires even a quarter of that.