One argument I would like to add to this original debate is that I have observed two types of developers: one type tries to stick to one programming language for everything (e.g. Java) and tries to write everythin in that language. They are specialist and they may accrue deep knowledge of the language versions, APIs and IDE(s). Another type of developer, in contrast, maintains active knowledge of a dozen programming languages (C/C++, Java/Kotlin, Python, bash, Rust, Go, PHP, JavaScript, ...), and is capable of delivering projects in each. They'd pick a language suitable for the task and stick with it for a project. They won't know any single language as intimately as the first type, but they benefit by virtue of their choice of language being more appropriate to the given project.