A well-optimized WordPress + Gutenberg + Kadence/GeneratePress site on managed hosting can plausibly match an Astro-on-Cloudflare site in CWV

Claim: A WordPress installation configured with Gutenberg-only (no Elementor/Divi/WPBakery), a lightweight theme (Kadence, GeneratePress, Hello, Blocksy), running on managed hosting (Kinsta, WP Engine, Cloudways, Rocket.net), can reach CWV pass rates comparable to an Astro-on-Cloudflare site in field measurements.

Evidence: DebugBear, rtCamp, and Windmill Strategy case studies all show this configuration in the 90+ Lighthouse mobile range with passing CWV. Combined with HostingStep's independent benchmarks showing managed WP TTFB of 365-470ms (vs Cloudflare ~45-50ms), the gap is real but small.

Confidence: Directional. No public head-to-head matched-content benchmark exists; this is a triangulation from multiple agency case studies.

Practical implication: don't recommend a migration on CWV grounds alone if the existing WordPress site is already on managed hosting and uses Gutenberg. Migration only makes sense if there are measured INP issues, integration requirements WP can't serve, or editor-workflow improvements worth the migration cost.

Threshold to revisit: if a head-to-head benchmark publishes showing the gap is >5 pp CWV pass rate at p75, downgrade the equivalence claim.