I am the author of BetterNether, and was contacted by someone with a culling issue (quiqueck/BetterNether#137). Upon testing I found that MoreCulling appears to introduce a problem with our custom meshes, in particular this one:

I would guess that the feet of the bowl present the issue. They have set a cullface for the bottom-face as you can see here:
https://github.com/quiqueck/BetterNether/blob/e2750dbff153c4cac0c5441fba44cb45761f9cc9/src/main/resources/assets/betternether/models/block/cincinnasite_fire_bowl_on.json#L88-L98

Is this an issue were MoreCulling does not process the model correctly, or do we have to change our model(s)?

While the report was made for 1.19.2, the Model is the same in most versions of the mod.

Can confirm this happens on my end as well. Hope a solution can be found.

In the meantime you can disable the culling for BetterNether as described here:
quiqueck/BetterNether#137 (comment)

@quiqueck Sorry for the late reply. Ive been really busy these days.
This is most likely due to the cull shape not being done correctly within the block.

Explanation on how to fix it and other possible issues here:
https://github.com/fxmorin/MoreCulling/wiki/Using-the-API#Fixing-culling-issues-on-modded-blocks

No worries, and thanks for the great wiki entry! I actually forgot about the CullShape property and was only checking the model files. So this helped a lot :)

Issue appears to be the same for the Ink Bushes as well.

This issue occurs with the betternether repawner statues as well when you look at them from a few blocks below them.

FireBowls and Respawner will be fixed in the next release, however I could not reproduce the issue for any age state of the ink bush. Would you happen to have a screen grab of the problem?

Only happens with the fully mature ink bush version for me.