Would Britain still build Vanguard if Hood survived?

If HMS Hood survived, would the Royal Navy still complete HMS Vanguard?

Probably yes; political and institutional inertia would favor completing a ship that embodied Britain's accumulated capital-ship knowledge.

Vanguard would probably survive the counterfactual even if Hood also survived the war. Britain's completion of Hood after the First World War supplies the precedent. In both cases, the ship embodied accumulated capital-ship knowledge that political and naval institutions would be reluctant to discard. Institutional momentum behind preserving and demonstrating the latest British design expertise would outweigh the immediate fleet numbers.