Digital "theaters" do not have the same limitations as physical theaters. The metadata can mark the page as R but include an additional indication that a PG filtered version of the page is available, via a different URL or a website setting that uses a cookie.
If the website doesn't want to make a filtered version than the metadata can mark the page as R with an additional indication that PG content is present on the page. The parent can manually select the PG content or someone will make parental controls that can automatically select or (like an ad blocker) filter for only the PG content.
Comments
Digital "theaters" do not have the same limitations as physical theaters. The metadata can mark the page as R but include an additional indication that a PG filtered version of the page is available, via a different URL or a website setting that uses a cookie.
If the website doesn't want to make a filtered version than the metadata can mark the page as R with an additional indication that PG content is present on the page. The parent can manually select the PG content or someone will make parental controls that can automatically select or (like an ad blocker) filter for only the PG content.