Who is the data controller when storing data in a blockchain? (immutable distributed data store)

There is a lack of consensus as to who is a controller / joint controller, further confounded by what processing is being undertaken on a given dataset at any one time. Blockchains, involve many different players and is unlikely to be an entity (and ergo a controller), in and of itself. You will need to apply the GDPR (and EDPB) definitions of controller to each blockchain you encounter, on a case-by-case basis. You know the familiar phrase – ‘There is no one-size fits all’! As an entity placing said data onto a distributed ledger, you are a (de facto) controller, but do you remain so, given the dilution of your powers?