Many people have their dev environments sitting on remote hardware and ssh in. Terminal sessions or an IDE aren't that resource-intensive, and that's all you need.
Yes. My laptop is not on the lowest end of the scale, but over the past week my IDE has alternated between vi and emacs on my VPS as I edit Python scripts. I don't need a lot of local power to do that - years ago I was doing that type of thing from VT100 terminals.
You don't even have to offload the processing to a server unless you're working with a compiled language. Python/ruby/node/any other interpreted language plus PostgreSQL, plus a text editor like atom, plus a couple browser tabs should all run together just fine on a chomebook. I was comfortable running a setup like that 5 years ago a single core 1.6ghz atom netbook. Nowadays my cell phone probably has enough raw horsepower to run all that, compatibility issues aside.