The same way he did Python, in a console. The only languages which may be a challenge to program in that fashion would be Swift, Objective C, and C# - because they are so tied to MacOS and Windows respectively.

A well set up Vim or Emacs is perfectly capable of writing Node.js, Java, C (side note - hilarious that you tried to use this as an example, given that C and C++ are probably written by a majority of developers in the console) and Go.

Developing using a remote computer is not developing in the iPad itself.

The point is that it's an equivalent workflow. It doesn't make the process of developing worse if you're used to those tools so why does it matter if it's 100% local?

We can assume if it's working for them then network connectivity isn't an issue (which is isn't for most of us, most of the time).

Since we're talking about the feasibility of using an iPad for software development, this seems like irrelevant semantics.

> For example, Node.js is one the top programming languages being used now

Node.js is not a programming language. It's a framework. I currently develop Node.js for work, and I always SSH into a remote machine to run tests and do development work. Developing Javascript, C, Go, and Java over a ssh connection is doable, one of the best options in the case of C and Javascript.