I would not buy a metered connection. It might end up costing me less than an unmetered one, but cognitively it weighs more as you said. I want a flat-charge XMBit/s hard limit, which translates to a total theoretical maximum of ZGB/month.

The power costs per GB sent/received are negligible, the money goes towards maintenance of the network and ethernet cable doesn't degrade based on how many bits pass through it. If too many people utilise the network, then just throttle them and start dropping connections from the more aggressive ones.

Perversely, I would be perfectly fine with you dropping my connections if I try starting 100 parallel downloads or charging me the same whether I download 1GB or 100GB this month, as long as it's a nice flat reliable fee.

Edit: about "that's how all utilities are measured". They aren't. Road tax is flat, but I can drive on the road for as long as I like as fast as the rules permit. Except it's slower when too many people do it at once. I want my internet to be like a road. (disclaimer: maybe road tax isn't flat where you live, but it is in many parts of the world, so please imagine we're talking about them for the purpose of the analogy. you may also need to pay a higher tax to use the highway, but it's still flat. it may also vary per type of vehicle but it's still flat.)