If through optimizing the software they can eliminate the stuttering which, like a pervious commenter, I also get, I really couldn't care less what level of WiFi it was. I mean, ANY of them are enough to stream audio. It isn't exactly a "high bandwidth" use case.
The OG, OG2 and mini will be far better served by attention to and fine tuning of their software. A push for more modern (more expensive) WiFi just for the sake of being the latest doesn't really serve anyone. Any WiFi, probably all the way back to B and G could stream audio without skipping and stuttering. The N in WiFi 4 provides more "wiggle room" and cushion, and WiFi 6E does have some improvements in latency, etc. But those aren't NECESSARY. Well polished software would could easily provide an excellent user experience even at the older specifications.
I have a bunch of mini's, and am thinking of getting an OG 2 now. I think they're great, but they do have some warts. Would love to see Apple do a deep dive on making tight, clean, polished firmware for them.