The items cause a lot of lag because if I'm not mistaken they check each gametick to see if they are colliding with other blocks (from 1.13 onwards the items lagging 4/5 times more than 1.12)

Do you have an example world and carpet setup you could share as an example?

I guess the issue is about a general item lag that is caused by having couple hundred item entites in a single spot.

maybe we can add anther chose to open or close to make item not more lagge, just like the chose "fast Redstone dust"

I think this is can be solved by using tweakeroo disableEntityTicking (or also you can use disableEntityRendering)

Use lithium to fix lag.

exactly