Under the new rules, businesses and professionals selling goods or services will no longer be allowed to accept or make cash payments of €10,000 or more.

This doesn't apply to private transactions, by the way.
Off the top of my head, I can't think of a single example of a legitimate legal business that would be done using cash in that amount.
So while there's definitely a danger of the rules being tightened over time, this specific change here doesn't raise my concern too much.
What bothers me more is the utter lack of any effective measure against the true problem in tax fraud – those who do it at a truly large scale still get away without any punishment or control, and in fact sit at the table when the tax laws are written.