I don't think you can generalize American fireplaces. Every fireplace I've personally encountered has been traditional wood burning and absolutely heats up the room well past the time the fire is actually lit (American Northeast). I haven't actually been in a home with a gas-burning fireplace.

But more importantly - the gas fireplaces are intended to look nice with minimal effort. They are explicitly not intended to change the indoor climate much if at all. They're usually built in very new homes that have dedicated, reliable climate control systems or in cities that don't require much heating.

I can agree with that last statement. Every house I've seen has had a gas fireplace, but I live in the metro area of a city that (in)famously only owned a single snowplow.

You have a slightly condescending tone here that I'm not sure is necessary. Perhaps they're "all-looks-no-function" because they're mostly meant to be decorative rather than functional?

Here, in Central Texas, my home has three fireplaces. Each designed to accommodate wood, but all have gas feeds that make it possible to run them without the smoke of wood fires. We don't run them for heat nor decorative effect. The are just architectural features of the house that some people might choose to utilize for the mood that a fire can convey.

They are a bit like windows: not energy efficient but nice to look at/through.

During the historic cold weather going on this week, I have no confidence that they would help if the power went off.

You are stereotyping a country of hundreds of millions that spans climate zones ranging from Hawaiian tropics to the arctic circle.

Yeah. There are decorative fireplaces. The Norwegian company Rais sells some great decorative ones.

There are also incredibly efficient cast iron stoves that some people use for heat. You made fun of them in another comment, but they are much more efficient than a fireplace, and can use a variety of fuels like pellets or gas in addition to wood.

Of course, there are also people that have a standard wood fireplace that you imply is in every Norwegian home. Most people don’t use them here since they are so inefficient, dangerous and illegal in cities due to the pollution.