(I'm not one of the authors of that paper.)

As far as I know there's nothing incorrect in the paper that needs to be retracted.

You can see one of the authors of the paper — Andrew Miller — being interviewed by a journalist about it here: https://cointelegraph.com/news/monero-transactions-history-can-be-revealed-and-exposed-research The journalist specifically asks "Say I downloaded a Monero wallet right now and got some and tried to send them for a transaction. How linkable would a transaction be today?".

Since some people posted speculations about my company's involvement in the research and our motivations, our company posted this statement: https://forum.z.cash/t/on-improving-user-understanding-progressing-tech-with-science/15387

By the way, check out the awesome block explorer that the paper came with: https://monerolink.com