It's not acrobatics. I simply don't think "free software" conveys anything useful to the general public — even the general tech public. Following it with "I mean free as in speech" every time doesn't help much either -- especially these days that needs its own extra explanation. Read this on Elon Musk and Twitter, for example. You might or might not agree with the thesis of that article -- but that's exactly the point. If you're lucky, maybe ten minutes later you're back to what you're trying to talk about.
People better understand the term "open source" -- they've probably heard of it, and it gives a better opening. You're right that it often has to be followed up with the benefits beyond code, but that's what I want to talk about anyway, not about the esoteric philosophy of "freedoms" or "software rights" or whatever. (Source: I talk to diverse groups of people about this stuff all the time. )
I can have those conversations. However, people tend to have widely disparate and strongly-held -- but not very well introspected! -- ideas of about the concepts of rights, freedoms, fairness, justice, and so on. It'd be helpful if people had something like this in their basic education, because without it there are going to be deep assumptions that end up with people talking past each other and. Sometimes fun, especially with a reasonably-sized group of people with good faith intention to understand each other better. But ... for a general tech interview? Nah.
Anyway, I do sometimes say "open source and free software" or "free and open-source software" for the right audience -- I think you'll find that in this interview, in fact. It's not like I'm allergic.