> Also why do people invent a new word 'transpile', when the old word already perfectly describes translating from one formal language into another?
The answer is... the old word ('compiler') didn't mean what it does today, back in the 60s, when 'transpiler' was coined. Compiler with its current meaning isn't a much older word than transpiler - they're near contemporaries (50s and 60s). Before that a compiler meant a linker.
> Also why do people invent a new word 'transpile', when the old word already perfectly describes translating from one formal language into another?
The answer is... the old word ('compiler') didn't mean what it does today, back in the 60s, when 'transpiler' was coined. Compiler with its current meaning isn't a much older word than transpiler - they're near contemporaries (50s and 60s). Before that a compiler meant a linker.
Your criticism doesn't match up with the history.