It's important to remember just how closely divided the Senate is currently: just 50 Republicans and 49 Dem or Dem-aligned Senators. They need 67 votes for impeachment. Assume all Dems vote for impeachment (actual charges are irrelevant). That means they need 18 Republican votes
I disagree with the conclusion because I think the most likely result of impeachment would just be a Dem surge and further tightening if Cathedral control