The speed limiting applied to the fix of [MC-147270] affects players in spectator mode.
Steps to reproduce
Change to spectator mode.
Go under a 1.5 or less blocks height space.
Press crouch, which is the key to decrease fly height.
You will be affected by the speed limiter while clipping through blocks. Speed will be back to normal once you're back in open space.
Linked issues
is duplicated by 3
relates to 3
Attachments
Comments 3

Fixed in 1.14-pre3.
Confirmed to be fixed in 1.14 Pre-Release 3.
Confirmed for 1.14 Pre-Release 2
Here is a video as example:
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