That's very interesting... I see you are in a superflat world where I was in an normal world and I was wondering if that made a difference. So I tried the command again, also in a superflat world this time and I seem to get massive amounts of lag there as well, way more than you seem to be getting
I'm sorry for editing the post so much, the formatting kept breaking for some reason
I ran a performance metrics debug test while this lag spike occurred and I've attached the resulting zip file
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