I thought almost all programmers created a language or two in the course of their careers or hobbies.

You can make a simple language very easily if you design the syntax carefully and restrict its capabilities. It all depends on what you need it for.

In my case I needed a way to create reports from a Turbo Pascal program (TP3 for DOS I think) without having to edit the program and ship a new version. So I made a simple report generating language. It had simple for loops, all variables were global, tokens were all separated by white-space, no user defined sub-routines or functions, a set of predefined procedures specifically designed for the report generating function, arithmetic expressions that were only allowed in assignment statements, interpreted not compiled.

It was actually quite easy to do but of course was not a general purpose language. These days it might be simpler to embed Lua.