You can try to generalize, but you will end up with a lot of logic on TypeHelper that really should belong to the types themselves. From a design perspective it's much better to let the types act on UNFETCHED_PROPERTY.

For HHH-12054 Closed I added to org.hibernate.test.type.TypeTest but blobs, clobs and nclobs are not tested there.

In the future (6.0) this will likely change and we can re-evaluate then.