Most Republicans are not turning on Trump, true. But it doesn't take more than ~5% switching from Republican to Democrat, to make Republicans never win a national election again.
Looking in from Europe, the immovability of US voters is quite bizarre to me. Most people I know don't have being a "Republican" or similar as part of their personal identity.
So on one hand people here hate the Democrat leadership (with good reason). But now when this guy is speaking out against the Democrat leadership, you criticize them for internal division?