Lab LCP 1.9s, field p75 LCP 4.3s — closing the gap

Lab LCP 1.9s, field p75 LCP 4.3s — closing the gap
Lab data (Lighthouse on a fast emulated device) said 1.9s. Field data (real users, CrUX p75) said 4.3s.
— Re-ran lab with 4x CPU throttle + slow 4G: LCP jumped to 4.1s, matching field.
— Real bottleneck: 380ms of JS hydration on median Android, invisible on desktop lab default.
— Deferred hydration of below-fold widgets.
Field p75 LCP: 4.3s | 2.4s
Takeaway: lab on default settings hid 2.4s; throttle to median hardware or the number lies.