Probably a bit, though I have noticed an upward trend in v6 support with ISPs.
When I was using Spectrum, was pleased to find they had (barely-passable) support, SLAAC wasn't a thing IIRC. Google Fiber has done well and so did AT&T's offering
Ok, fair enough. If Spectrum and AT&T both support v6 now (edit: Comcast/Xfinity too!), then that probably does cover a good portion of the wired ISP market.
When I was using Spectrum, was pleased to find they had (barely-passable) support, SLAAC wasn't a thing IIRC. Google Fiber has done well and so did AT&T's offering