This summary is not the rule. The rule text controls.
Lawyers can't lie about judges or other legal officials, or make careless statements that turn out to be false. This means a lawyer can't publicly attack a judge's honesty or qualifications if they know the claim is untrue or if they didn't bother to check whether it was true. This applies to sitting judges, other public legal officers, and people running for judicial or legal office.
The rule also covers lawyers who are running for judge themselves. If a lawyer is a candidate for judicial office, they have to follow the rules set out in the Code of Judicial Conduct that apply to judicial candidates.
The point of this rule is to protect the public's trust in the legal system. Judges and courts only work well if people believe they're fair and honest. Lawyers know the legal system better than most people, so when a lawyer makes claims about a judge being corrupt or unqualified, the public tends to take that seriously. This rule stops lawyers from misusing that credibility to spread false information.