I think you might be surprised at how many people do know what a join is, they may call it another name, but it's not a hard concept to understand. It's a very common thing I've seen non-technical people do and use.

No, but most of them know what a v-lookup is, and almost all of them know when they need the result that a join accomplishes.

Yeah, one of my old coworkers was ecstatic when he learned about joins. He'd been downloading two tables and then using vlookup to join them in Excel. Using actual joins sped up his workflow a lot.

Thats why their non-technical user abstraction is a worthwhile investment for businesses who want their devs to be doing real work instead of pandering to the latest whims of a product director / marketing exec

99% of business users know what a VLOOKUP is.