Um, Red, CZJ made a 28/8 Tessar for the Contax and a 55/8 Tessar for the VP Exakta. Both pre-WW II. I'm not sure that either qualifies as mass-market, they certainly weren't inexpensive when new.
Dan, sure, but those are interchangeable-lens "system cameras." There were wide angles for a variety of such systems well before the period of the 1970s; the ones you name are likely some of the earliest. Probably none of them were mass-market or relatively affordable until 1960s SLR and wide-angles came along. The OP asked about (roughly speaking) fixed lens 120 folders with wide angles that aren't expensive exotica, which you confirmed didn't really exist. And my feeling is that prior to the 1970s, there were hardly any fixed lens cameras with wide angles that aren't exotic (even relaxing the "120" and "folder" requests).