The problem is the sort of "elitism" they oppose. It isn't "the works of one who grew up poor's ideas should be considered on their own merit just like one who was born wealthy". It is "What do biologists know about vaccines? Numbers are soulless lets go with what feels right." Plus even if the populism is 100% natural it may still be exploited by any willing to use it as a ladder. Being "for the people" has made no difference vs "for religion" or "for our geopolitical grouping".

Not helping matters is anti-elitism as a crab bucket mentality where they complain about the geographically near comfortable instead of the actual powers. Blaming the miller for their problems instead of their lord.

Even when not hijacked populism often fails to actually fix anything, it may be its refusal to acknowledge reality in its groupthink and search for easy solutions, dislike of nuance and not wanting to hear that the things they had just aren't sustainable or what they would need to do to make it so.

This used to be called demagoguery, and is very popular in dictatorships.

Not only have physical and financial poverty increased in the West - the UK and US have non-trivial numbers of people literally starving to death - but so have poverty of education and poverty of opportunity.

"The poor are lazy and deserve it" arguments are naive, irrational, self-serving - and a populist oversimplification themselves.

The reality is that when education improves, nepotism and corruption are constrained, and wealth becomes more widely distributed and accessible, economies boom and the poor do much better - unless the growth is sabotaged by external influences, as it sometimes is.

The concepts of populism and demagoguery are also being cynically used to target those movements that do prize nuanced, strategic planning for the future that happen to also conflict with wealthy interests. The whole horseshoe theory is an attempt to overly conflate the group of "people who want significant change" with "angry, ignorant people". It's a counter-simplification that's just as pernicious as someone blaming an immigrant for their problems instead of much bigger systemic processes. As you mention, education is critical and much of it has been steadily stripped of crucial, system-challenging concepts, much like food has been stripped of nutrients and replaced with empty calories. Getting more of such anemic education isn't any better for social health than Big Macs are for bodily health. We criticize "useless" degrees or fields, but have also severely unbalanced dissemination of knowledge to favor just what businesses desire and not necessarily what is good for a society.

Populism is 'supporting the concerns of ordinary people', demagoguery is 'apealing to popular desires and prejudices at the expense of rational argument'. Distrust of populism itself is misplaced distrust, since while these two concepts do appear at the same time on occasion, I'm not sure of a causal or even correlated relationship.

I think it is more a matter of how populism is defined: the policies or the stated goal?

Look at the USSR and the way they treated their workers. Taken for granted and undersupplied, given grandiose mandates to live up to from the uninvolved above to deliberately gives lung cancer to union leaders via minutes long xray. The USSR was "for the workers". The Technocrats weren't really scientific or engineering based, just a moronic faschiod cult which called for a power based currency and no interest or accumulation - ignoring the value of other inputs or accumulation of growth. And then there is all of the violence committed in the name of religions calling for peace....

The point is never trust the pretense. Populist movements/groups are untrustworthy by defining themselves by the pretense instead of the policy. This does not apply to some policies called populist.

Moving up the bonus payment dates in the Great Depression, safer working conditions, raising the minimium wage, shorter hours, Roman land reform after the farmland had been illicitly shifted past the legal limits per owner, even more radical goals like Georgist "only the value of the land itself is taxed - scaled appropriately", shifting to direct democracy are all fine - a given policy may or may not work as intended but they are not an easy direct road for some megalomaniac to power.

Populist groups are untrustworthy for the same reason as theocracies. It isn't operating upon the basis of say treating fellow man as a brother that is bad but the actual practices.

The urge to populism is natural, a result of a sense of getting screwed over (which is actually happening). The focusing of that populist urge, on the other hand, is subject to exploitation by certain powerful elements.

Don't confuse the two.

Most populist leaders in history have been members of the elite.

Julius Caesar, after all, was far from poor.