I have heard "partner" for traditional relationships for a couple of decades. It all depends on where you live. Enlightened liberals like to say it as a way to normalize non-traditional relationships. I heard "partner" way more than "husband" or "wife" back in Santa Barbara. Here in sticksville, I don't think I have ever heard someone say "partner" unless it's their business partner.
In fact back in Santa Barbara, at least a couple of times, somebody thought I was gay because I said something like, "I'm hooking up with my partner this weekend to go quail hunting". Because boomers call guys they do stuff with partners and buddies*. But just like "gay" no longer means "happy", "partner" apparently doesn't actually mean "partner" anymore.
*Also, "hooking up" doesn't mean what it did when I was a kid. Don't even ask me how many times I nearly got into sexual harassment trouble at work because I said I was hooking up with a female coworker.