[Ragnarork]

Aside from "the right tool for the right job" kind of conversation, there's one inherent aspect to chasing the most popular language (given that you find an actual ranking that's put up meaningfully, which I don't think the TIOBE index is): you may find more people able and willing to work with it, which can sometimes be a feature.

I've been in a company which had a major refactor need, and they took the opportunity to slowly convert their backend from PHP to Go* because they couldn't find any good PHP developer (let alone any willing to work in PHP). For the actual project, it kinda worked, but for the recruitment, it went from not having any applicants / very mediocre people, to having way more people applying, and a few competent ones in that pool.

* As to whether that was the right choice, that's a completely different topic...