Or maybe there's just not a lot of AI in their main search product (for whatever reason). They seem to be pretty good in other areas (Translate, Cloud speech-to-text, Alexa etc.)
For the matter of translation they actually aren't pretty good. DeepL outsmarted all of them (at least for the supported languages). Given the resources thrown at this problem by the different companies I would even say the results of Google, MS and such are actually quite disappointing. (And I don't think one could say "but this companies did the upfront work" as the basic ideas are something 60 years old).