Sure if your value add is content then go ahead and use mature tools within the paradigm, but if you want to cause a so called "paradigm shift" then you'll need to understand where the progress is happening and what kinds of opportunities it creates.
Ocaml for example is looking more and more enticing. Standard meta language is used by academics and programming language theory is developed in it. Meaning that it has a good long term trajectory (along with lisps I suppose).
Of course we are about to grow out of syntax, soon it'll just be another config param in your editor.. but I don't think these "obvious choices" you list will all be as well positioned w.r.t. that change.
Right now it may be harder to agree with me than with you, but that makes me think of a hn thread I was reading recently where people didn't want to admit to being programmers (in public / to strangers) because the perception is starting to be that what we do is immoral. Sufficient mastery of programming will make it a boring thing that everyone knows how to do but lowering the bar to that point won't happen within the web paradigm we currently inhabit. We'll see if wasm brings us closer but I think it will take more than that.
Anyway, I'd say your advice is good but not great. A CTO should be able to assess which tools fit the problem they have for the timescales they're considering. If they're swayed by your comment (or mine for that matter) then they're not fit for the role. The person you are actually talking to is someone who is building a company that suffers tech while the core business is something else or a company that is meant to be sold to some giant.