This attitude (replacing a lean and fast terminal, by one rendered using a web browser engine) is exactly why modern machines that are 1000x faster and with 1000x the memory still seem to be slow for basic tasks.
Of course, it's a free choice. You can waste resources by replacing small programs by browsers ;). But it's reasonable that many people find it a waste.
Well thats subjective. I might not be as cool as you but I get my work done using these tools.
If it starts to get into the multi-GB range it can hurt to download, but below that it's all identical to me. If it means that i don't need to run a specific version of a library installed globally on my machine, and i don't need to manage a big chain of dependencies myself, and it runs on multiple platforms, i don't care if it's 1mb or 500mb, and i don't care how many copies of it I'm running.
My ssd has 60gb remaining on it after a few years of daily use and i haven't needed to worry about program space yet.
When I check the battery status on my Mac, only Chrome is listed in the "Apps that use significant energy" list.
So, for one Javascript-written terminal app, you can install a full Linux system with X and a window manager 10 times (Hyperterm.app is 122 MB).