There is a broader ethical discussion of how to treat data, nominally public, that is increasingly collected, persisted and analyzed indefinitely by adversarial agents. It seems clear to me that a more nuanced categorization is required. This data is not public in the same sense as an uttered word was in a town square a hundred years ago.
Imagine being denied job opportunities because some company has analyzed the careers of the last 25 generations of your ancestors and deemed your lineage to be inadequate?
You mean maybe for your LinkedIn general profile info to be public, but not for the old profile data or the metadata of when your changed what to be public. It's not per se secret or hidden but it's also not intended to be kept and processed.
This is also a clear case where GDPR would come in. This is personal data, whether intentional or not, and the scraper is obliged to conform to EU laws if they scrape data on EU citizens - including eg information rights and deletion.
Imagine being denied job opportunities because some company has analyzed the careers of the last 25 generations of your ancestors and deemed your lineage to be inadequate?