Fair enough - it is definitely not the case that ALL customers can tell the difference, but some do. And I'm pretty sure that some competitors seed those questions, if only to eliminate some of the competition. "Ask your other photographers if they do X or Y."Not to get too far off topic, but your comment makes me curious. I can see editors and other photographers getting snotty about gear, even though they should know better. Lots of gear snobs out there. But I'm wondering about the clients. Are these companies or individuals that you've noticed won't work with you based on not using the latest gear? I wouldn't expect most individual consumers to understand the difference.
As one of the other respondents said, if I can provide a pin-sharp 20x24" print on fine art paper in your choice of matting and framing at a competitive price, why do you care if I used a 10-year-old full frame DSLR, a 6-year-old sub-full-frame DSLR (gasp! the horror!) or a top-flight 2022 mirrorless? For that matter, if I do it with a film camera, would you know the difference? Honestly, it's just as (ir)relevant to those consumers as "does your digital darkroom run on an Intel, AMD or Apple CPU?" But for me running a business, that D800 was paid for ten years ago. If I can accomplish my business goals with it, why should I be dropping $5500 on a Z9?
At the end of the day, this is just like "gee, your phone is an iPhone6... you ought to get with the 21st century."