No one is calling Christians stupid. The nutjobs that want to tear down our secular society and replace it with a white Evangelical ethnostate are telling Christians that their political rivals are calling them stupid. They're the suckers for the conmen, and at this point, it's not worth attempting to rationalize debate.
This demand for one sided niceness that amounts to submissivity was is is contraproductive.
The meat of the article are actual bad acts. You are just using the tone to distract from the actual accusations.
This is only really true on the political level, not the cultural/social level. Politicians on the left have been significantly more respectful than their counterparts for a long time now. But the same can't really be said for the sentiments of their voter base or the media/education curated towards them. For a large amount of people what they see and experience in their day to day lives does more to color their beliefs than what a politician says that they have no relation to and might see a few sound bites of here and there running up to an election.
The left has to learn that telling a prospective voter repeatedly that they are the enemy won't make anyone want to support them unless they're already believers. It'll just push them towards the side that's offering to call them an ally.
And that's why they're losing.
The problem is not so much wanting to coddle up to the fire-and-brimstone fundamentalists. It's that a lot of people who used to have what would be considered "standard", middle-of-the-road religious views have been told, again in subtle and not-so-subtle ways, that they're stupid. Whether you believe this to be true is not the point. Calling a large portion of the country stupid is a great way to push them into the arms of an extremist.