Not Allowing Miner to Read the Data in the block


i’m currently working on the topic blockchain for my mémoire.

Even if transparency is an advantage of the blockchain, it is also a problem for company that want to use blockchain but can’t affort showing their data.
However they like the security provided.

Here is my question
could we consider a blockchain used by a company where miners help secured the chain with their computer power but can’t read the data in the block ?

it seems to me that not allowing access to the data in the bloc is an obstacle to "mining/securing’ the chain but i would like to be sure about it.

I thank for your help and apologize for my english level