Player can still move at normal speed and sprint when "crawling" in a one block tall space

The bug

When the player is in a space that is just one block tall, it can walk and sprint at normal speed, which seems illogical since that is not possible if the player is sneaking in a 1.5 blocks tall space (MC-147270)

To reproduce

1. Put a trapdoor at a wall and open it

2. Go inside of the trapdoor

3. Close the trapdoor while you're standing in it

4. You're now "crawling"

5. Dig a tunnel

6. Walk into that tunnel, and try to sprint

7. ❌ You move at normal walking / sprinting speed

Video