I agree with the overall sentiment. Plus almost all cases I run into performance issues with e.g. Python in general web development, that main problems were how the code was written, not what it was written in and being bottle-necked by the database.

That said I disagree a bit with saying it is a a solved problem unless you are Google-scale. In developing countries if you are in a small company without big investors, you need to do quite a bit more juggling with infrastructure budgets once you are past MVP compared to for example where I'm from Switzerland.