I noticed this because I was preparing to make a bee farm for 1.17. Carrying a lot of bee nests/hives, all or most of which have bees in them, within a shulker box, will create lag anytime you carry it in your hand. That's pretty much the extent of the issue, I haven't done much testing, this is on the most current version of Minecraft Bedrock for the PS4 as of writing. It may affect other versions or platforms.

It would seem that the game has a hard time keeping track of the fact that there are so many bees within a shulker box, not to mention that some are adults, some are middle stage, and some are still in first stage. This strikes as a bit odd because the game has no problem rendering all of the bees when they're actually on screen and flying around, just when they're all stuffed in a shulker box, and specifically when said shulker box is held in hand, for some reason.