I agree that "properly working lambda expressions were only available in Lisp until recently" is perfectly idiomatic, but easily misunderstood, English. I believe that the suggested fix "properly working lambda expressions were only available in Lisp since recently," which is what I was responding to, is not idiomatic. Claims about what is and isn't idiomatic aren't really subject to definitive proof either way, but it doesn't matter, because the suggester now agrees that it is not what was meant (https://news.ycombinator.com/item?id=43653723).
To be clear, the construction I’m endorsing is: "were available only in Lisp until recently", which is the construction that my editors typically proposed for similarly ambiguous deployments of "only". The ambiguity in the original placement is that it could be interpreted as only available as opposed to available and also something else. My editors always wanted it to be clear exactly what the "only" constrains.
