What could be the issue for "Limit Adult Websites" not working in Screen Time?

Hi all...I have Screen Time configured and the Content & Privacy Restrictions > Content Restrictions > Web Content option set to "Limit Adult Websites". My understanding of this setting was that it will block a known list of adult web sites maintained by Apple. This does not seem to be the case. I tested with a well known adult website (beginning with "p") and Safari didn't even slow down before displaying the site.

Before a well-meaning Apple support tech chimes in, let me add:

• Screen time is set up fine and is working in other respects.
• I am updated to the most recent iOS.
• I am very well versed in the configuration of Screen Time.

All I seem to be able to find online is either information saying "just set it to Limit Adult Sites and voila it works!" or other asking the same question with no solution in site (going back for for years.)

I suspect that it will boil down to "call Apple support" which I've done for other things and usually it it a long arduous process that typically does not yield any positive results so I thought I'd add my question about this to the long, long tradition of parents who have asked it before me.

Any help is appreciated.