I haven't been able shear these blocks with shears from mods such as Ceramic Shears and Stone Age's Bone shear, regardless if "noBlockDropsWithoutCorrectTool" is true or false. However the vanilla Shear still works as intended, and the modded shears still work with most blocks such as vines, leaf blocks and for some reason ferns.

this does break compatibility with Stone Age as that mod relies on its bone shears to collect grass specifically in order to progress through it.

this has been tested with:
notreepunching-forge-1.16.5-4.1.2 (removing fixes this issue, which is why I assume there's a problem)
stone-age-1.16.5-1.3.1 (currently latest as of writing, and it's associated library is ages-api-1.16.5-1.2.0)
ceramicshears-1.4.0-1.16.4+ (currently latest as of writing)
BetterShears-1.16.4-2020 1.0.3 ??? (this one was tested but it was inconclusive with this issue as it add shears that doesn't even have the forge:shear tag let alone work by itself)