You're omitting a very important point: the heat sources themselves. The heat for the entire city doesn't come from a single power plant. It is distributed over many heat generation plants throughout the city, some dedicated solely to district heating. I don't think any spot on that map is more than a few km from a heat source.
To be fair, the vast majority of Helsinki's district heating system is powered by three combined heat and power (CHP) generation plants in Vuosaari, Hanasaari and Salmisaari. You're right that there is also 11 dedicated water heating plants to supplement the CHP supply in very cold weather or times of high demand, but they are supplementary.
You can sort of tell from the other responses, but really the core of this argument is not the one you think it is: You think this means it is less appropriate for New York because of this fact. It is the opposite. Your population density is higher, so these types of solutions are easier and more cost-effective. This makes the fact that you don't already have it seem even more incompetent, which is the opposite of what you wanted to achieve.
Consider it's a nation that reinvented a crappy version of a metro with bunch of teslas in a very unsafe tunnel, I don't think you can expect reasonable answers. /sarcasm
I know it's hard to develop actual efficient solutions due to the cost of buying land, creating new infra. So you go for the cost efficient route instead of the practical efficiency.
In finnish, the term is ”kaukolämpö”, literally ”far heat”.
You dont heat a ”district”, you heat the entire city. I mean, electricity wires go everywhere, why not heating pipes.
And so the network for Helsinki looks like this: https://twitter.com/energiahelen/status/1511998227008176129?...
The red lines is the heat pipe network, it covers the entire city.
When Americans talk about ”district heating” they miss the scope of the thing.