Diagnose why rich snippets aren't appearing

[yourdomain.com/recipes/banana-bread/] has Recipe schema implemented (paste below),
the Rich Results Test shows it as valid with no errors, and it's been indexed for 3
weeks, but no star rating or cook-time snippet is showing in search results even
though a nearly identical competitor page shows one.

PAGE URL: [yourdomain.com/recipes/banana-bread/]
SCHEMA JSON-LD (paste the actual markup): [paste here]
RICH RESULTS TEST OUTPUT: [valid, no errors, no warnings]
COMPETITOR PAGE THAT DOES SHOW A RICH SNIPPET (URL): [paste here]

Diagnose this the way someone who knows "valid schema" and "eligible for rich
results" are different things would:
1. Confirm the schema is not just syntactically valid but actually complete for
   Recipe rich results specifically: check for recipeIngredient,
   recipeInstructions, and aggregateRating with a real reviewCount, since Google
   requires more completeness for the visual snippet than the Rich Results Test's
   error-free status implies.
2. If the aggregateRating is present but reviewCount is very low (under 5-10) or
   looks synthetic (suspiciously round numbers, no corresponding visible reviews on
   the page), flag that Google may be silently declining to show it due to a
   trust/spam judgment, not a technical error, that's a common cause the testing
   tool won't tell you about.
3. Check whether this is a site-wide trust issue rather than a page-specific one:
   rich results are a privilege Google can withhold from an entire domain if it's
   seen manipulation elsewhere on the site, even if this specific page's markup is
   clean.
4. Rich snippets are also just not guaranteed even with perfect markup and no trust
   issues, Google decides whether to show them per-query based on what it thinks
   helps that specific SERP; say so plainly if nothing above explains it, rather
   than implying there's always a fixable cause.
5. Recommend a specific next step: fix the schema completeness gap, wait and monitor
   since eligibility isn't a guarantee, or investigate the account/domain-level
   trust angle.