Does the permanent and unchangeable nature of transaction records on a blockchain compromise an individual's right to be forgotten or to erase their digital footprint?

While information on blockchain is immutable, the context surrounding it is not. You cannot delete a piece of information from the blockchain, but if you are the owner of a piece of content, you can change who can or cannot see it. Instead of deleting it, there is an operation known as ‘tombstoning’ which marks a piece of data as obsolete, and inaccessible to anyone except the author. Since you own your content, and are the only one who has the private encryption key to make it readable, you can choose who can see it - and change this over time.