HTTP/2 vs HTTP/3: head-of-line blocking on lossy networks

HTTP/2 vs HTTP/3: head-of-line blocking on lossy networks
H3 over QUIC helps a specific case: packet loss.
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H2: one TCP connection, multiplexed. One lost packet stalls ALL streams (TCP head-of-line blocking).
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H3 (QUIC over UDP): independent streams. Packet loss stalls only that stream.
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Measured: on a clean wired connection, H2 vs H3 LCP delta ~0-30ms (noise).
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On 2% packet loss mobile, H3 cut p75 TTFB ~15-25%.
H3 is a mobile/lossy-network win, not a desktop win.
Takeaway: H3 pays off above ~1% loss; on clean links it is ~0ms.