One thing that's important to understand is that there a practical difference between "password exposure" and "more risk."
You can say with certainty that submitting a site to plaintext offenders results in additional password exposure. This fact is not in question.
Whether it results in additional risk, however, is more nuanced. If the site does nothing about it, and you, and other users continue to use the site as if the flaw was not known, then the additional password exposure does indeed result in additional risk. If, however it leads to changes in behavior, e.g., some users decide not to re-use passwords they would have otherwise re-used on this site, (more likely) or the negative publicity leads the site to improve the security of the system, (less likely, but possible and a huge reduction in risk if achieved) then the equation changes to somewhere between not so clear, to a definition and significant reduction in risk.
So it isn't as cut-and-dry as one option is right, and the other is wrong. Risk, by its very nature includes a component of the unknown, which is the likelihood of eventual exploitation, so ultimately it comes down to a judgement call.