Some notable things that stood out in the article are:

Even baseline responses from a "good" persona would rate quite high on the toxicity scale the researchers used.

There seems to be broad bias from all personas (and no-persona responses) towards certain topics of race, gender and politics.

The legal consequences of whether this could be considered defamation are interesting to consider as well.

Not surprising: The Nixon persona was 3x more toxic than Nelson Mandela.