Commands unresponsive at high tick speeds

I set the tick speed really high to test the copper degrading, but all that seemed to do was make commands unresponsive. Breaking and placing blocks seemed fine though, and no lag was introduced. System fans did not speed up. World saving took a lot longer than usual, so it was killed via MultiMC.

actions used in order:

world creation

messing around with creative

/gamerule randomTickSpeed 1000000000

[commands unresponsive past this point]

/gamemode spectator

/weather thunder

/gamemode spectator

/weather thunder

world saving

instance killed via MultiMC