When getting a shield with the command /give @p shield[use_cooldown={seconds:0.05}] 1 the cooldown on disbale does not change to 1 tick and remains at 5 seconds. Additionally the cooldown value cannot be set to 0 or disable another way.
MC-300032
use_cooldown component does not affect the time a shield is disabled for
Open
1
I do not believe
use_cooldownis intended to affect the time the shield is disabled for. If there is a bug is that the shield is not placed on cooldown after it is lowered, as the spyglass is (unless you switch away from it, which is another bug). Nevertheless I can reproduce this so I will confirm and retitle the issue.