Yes populism is overly broad - I think I'll reword this with a more specific example. You're right that MAGA is a better example - but do they even engage with their political opponents? They seem to mostly just sort of yell them down. Maybe my theory is wrong?
Religion is a good idea too - you're right that this is broader than just political ideologies. I'm a bit averse to wading too deeply into the culture wars, my attempt was to try and describe things at a meta level, or at least try to remain not too overtly partisan, so I was wary of attacking people's religion etc too explicitly.
You can acknowledge critics are deluded or self interested whilst also admitting they have some substantial points - this is more in the vein of using that as a justification to ignore all criticism; even valid criticism.