If you hold down the sprint key while in a boat you will go faster. I don't know if this is intended but if it is if you double tap w it does not go faster.
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It does not go faster, it just zooms out like sprinting would. + this is INTENDED?!?

Found another ticket of that issue : MC-30431
If intended or not, can be resolved there.

Thank you for your report!
We're resolving and linking this ticket forward as a duplicate of MC-257082, as that ticket contains more detailed information and/or has already been triaged by Mojang.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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Intended.