Date Taken in Explorer and DO

11.19 came out June 10 and the post mentioning future versions was June 29, so the post definitely didn't mean 11.19 would contain the fix.

I believe current Opus 12 betas have the proposed fix, if you want to give them a try.

12.0.8 from July 1 included this change in the release notes:

When setting EXIF tags in pictures, Opus will no longer use UTF-8 for fields that never require it (e.g. "Date Taken"). This is to prevent compatibility problems with software that has trouble with the UTF-8 BOM header in certain fields (e.g. Explorer).