I think whether it's faster to code directly depends on many things:
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skills: as designers become more specialized in Ux and interaction design, code has become lower priority
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the design maturity of the project. Already have a design system with components and styles? Easy to whip up a page without sketching/doing mockups. Otherwise moving things around might be more difficult in code
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the needs of the team . Does getting html/css make the devs lives easier? Can code be shown to stakeholders? Can feedback be gathered easily? Can iterations be made? Compared? Tested?