The sentence "language choice matters far less than we like to think", which means something like "switching between most pairs of languages in most situations doesn't make a big difference", and your examples which mean "there exist pairs of languages as well as situations where switching between them makes a big difference" are completely compatible.
In fact, I would say that the latter is not interesting because of course we know there are situations where high-performance languages are more or less appropriate, but the interesting question is whether languages that have similar aims and performance, and differ mostly in their linguistic features make a big difference.
> In my experience
Unfortunately, people will also support the effectiveness of homeopathic medicine based on their experience, and much more enthusiastically. I'm not doubting your sincerity, nor even the facts of your situation, but this doesn't count as evidence. On the other hand, the fact that different languages are tried in different places, in an industry with strong selective pressures, the fact that no single language or paradigm completely overtakes all others is evidence in favor of there not being a very big bottom-line impact.