How cruiser speed shaped Iowa and early carriers

Did Iowa need greater fast-battleship speed because cruisers themselves were reaching 32 knots?

Yes. Fast capital ships needed to support the cruiser line, whose speed also influenced early carrier requirements before carriers began setting the pace in return.

The fast capital ship had to operate with and support the cruiser line. Cruisers approaching 32 knots therefore helped drive higher battleship speed. The same relationship initially shaped carrier requirements because carriers belonged to the scouting force. The relationship later reversed as carriers' operating speed increasingly governed the cruisers accompanying them.