You're forgetting that the Left is able to collectivize across sub-ideologies yet the Right can't because the former has collectivization baked into the way they operate and conduct policy. It's how they were able to usurp the religious right's thirty-year hegemony over culture methodically within a couple decades. It's not necessarily ideology that allows the Left to overlook its own hypocrisy, play by its own rules and constantly shift rhetorical goal posts, but it's also the fact that the deck is stacked in their favor now. These are the same people who, twenty years ago, were bitching about the Right's hypocrisy and desperate need to retain its slipping power, simply because they were envious of the power that the Right wielded; they have now become everything they used to despise without a shred of irony.
With all that said, infantilizing politicians at the expense of the Left doesn't have the same bite to it the way the Left does it to the Right. Their stranglehold on mainstream media allows them to control the narrative to such an extent that it makes the Right look foolish while the Left doing the same thing either gets downplayed or outriht swept under the rug. Following the 2016 election, you had a bunch of Brits across a fucking ocean with zero stake in our politics flying a giant parade float of a big orange baby through the streets of London that got media attention across the developed world. If the Right did the same thing, not only would the Left be clutching their pearls and take the moral high ground at every turn, but a lot of people on the Right would be dismissive of it too.
You can't win with their tactics because they will just spin the narrative against you, and you will look like a massive faggot to your own constituents.