430 lines of overly verbose BF to boot. You could delete 1/3rd to 1/2 of them by simple tricks the author hasn't used for readability reasons.
It's not the worst language if you're willing to work within the constraints and frankly, more readable than a lot of C++. My own editor (written many years ago, no meta interpreter) was 113 characters.
Yes, there's always space for optimization in Brainfuck programs. We haven't used some of the optimization opportunities for readability, as you've said. But we might have missed some optimization spots too, so feel free to open an issue or pull request if you know how to fix that!
Also note that 430 lines is the code compliant with our bd.style: heavily commented, unambiguous, modifyable. You can always minify the code and it'll be some 1K commands, which is pretty small for a text editor.
It's not the worst language if you're willing to work within the constraints and frankly, more readable than a lot of C++. My own editor (written many years ago, no meta interpreter) was 113 characters.