In fairness, it’s not just Pelosi who is weak on an impeachment inquiry. Ro Khanna isn’t down for it either. If reporting is right, most of the Dems on the Judiciary Committee are for it, including Nadler, but there are divisions in the caucus.
From my vantage point, the waffling is stupid. Nixon won a huge election, but an inquiry was eventually opened nonetheless. We forget now, but initially leadership was wary of impeachment in 1972-73 too. Eventually the American people, and congressional leadership, came around after the Saturday Night Massacre. Congressional inquiries made the case though.