Though you're right that the old house likely had a wood burning heat source, but I'd imagine that there were times when wood was scarce. And that 150 year old fireplace would have sucked air out of the house, bringing in cold air through every air gap.
I looked it up, and wood has an R-value of around 1.4 per inch, so a log cabin with 6" walls would have an R-value of around R8, current building codes in Texas specify R15 for walls, R38 for roofs.
Single-pane windows have an R-value of around R1, energy efficient double panes, around R4 (triple paned can hit R9) so even though there are a lot more windows in a modern house, they have better insulation.
It also requires somewhat specialized (read: niche and expensive) heating and cooling equipment, since there is so little air movement into and out of the house, and requires so little energy.
Oh, and ironically, when the power's out in a passive house, you need to open a window to ensure you don't over-humidify the house with your breath.
But for those being very casual about other people sitting around in 25 degree temperatures, that's actually fairly chilly especially if you don't have the clothing and bed coverings for it. And I say that as someone who lives in New England and has done winter camping.
Could I manage modulo piping concerns? Sure. (And I know you can drain pipes but I'd hate to be in a situation where I felt I had to do so in an emergency situation without electricity and then fire things up again when the electricity came back on.) But you're talking about huddling under covers if you don't have wood burning heat.
The other part was fine with one 2kw heater for the night. The whole thing was pretty scary. I'll make sure our next house has 2 fireplaces. One m3 of firewood will keep you going for a couple of days, and more importantly: your pipes won't crack.
They live in apartments that don't allow grilling so they never thought to buy one. And it being the winter, not many people who do grill in the summer have charcoal for winter grilling.
So when the power goes out, they can't cook anything on their electric ranges. If the water shuts off, that's even worse. Frozen food is useless if you can't even thaw it, let alone cook it.
Initially the weather reports I read said the winter storm warning only extended to Monday afternoon and now it's to Thursday, so lots of people didn't think to extend their emergency supplies to Thursday, and most probably didn't think they'd be without water and power.
I'm really lucky in that I have both water and power, but many are not. You really should not be judging people according to what the most privileged suburbanites can adapt to.
It’s like if I went to Canada and started shitting on people unable to deal with 110f weather without electricity .
Without adding heat, you're still not going to stay warm for long though. my window may have been bent so it couldn't close in winter throughout child hood, but we still had a heater on.
Watch out for your windows. Hanging stuff to act like curtains will help
Houses were designed very differently 150 years ago.
Lower roofs, fewer windows, huge thick drapes or tapestries on the walls, animal skins or carpets on the floors.
9 ft windows (double pane or not) on all walls is going to leak out a lot of heat.
Most importantly, fireplaces. Houses had fireplaces, and rooms were designed around a central fireplace to keep everyone warm.