I've supported v6 on a few small sites hosting OSS projects for almost a decade now, and I kept statistics over the years. The increase in v6 adoption has been glacial. Less than 1% increase per year.

My own connectivity at home doesn't support v6 due to my ISP. At work, v6 is so badly managed it's the first thing we rule out when diagnosing connectivity issues.

Kind of a sad state really. I wish v4 prices increased tenfold, not barely double.