It doesn't need to be "always true" for a tendency to produce conflicting objectives no sane legislator would ever choose (and making them much more difficult to repeal) to be a potentially crippling weakness of direct democracy.
Perhaps experience with being consulted is why the Swiss appear relatively sanguine about a referendum vote to impose quotas on all immigration being creatively reinterpreted by its trade-prioritising government as just introducing job preferences for Swiss nationals in times of high unemployment and tightening residency permit criteria. That's certainly a course of action which would be expected to create much more unease in other parts of Europe; the furore over whether prioritising Single Market alignment in the UK's future relationship with the EU over an assumed preference for immigration restrictions that wasn't even on the relevant referendum ballot paper is a notable contrast. But I'd imagine there were aspects of the Swiss political psyche other than "maturity", "long term vision" or experience with referendums which made them relatively unenthusiastic about an impractically-high UBI proposal, high minimum holiday entitlement and supremacy of Swiss law over international law and relatively enthusiastic about banning minarets, allowing greater surveillance powers and [until remarkably recently in some cantons] restricting the franchise to men. Californians certainly don't have a particular shortage of referendums either.
You made the generalization that people will always vote for shiny and expensive stuff, I gave you an example it is not always the case. I never said direct-democracy is a bullet proof system that always ends up deciding reasonable laws. Taking the case of surveillance law as a failure of direct democracy is not relevant as a majority of non-direct democracies countries passed far more privacy invasive surveillance laws around the same period
Perhaps experience with being consulted is why the Swiss appear relatively sanguine about a referendum vote to impose quotas on all immigration being creatively reinterpreted by its trade-prioritising government as just introducing job preferences for Swiss nationals in times of high unemployment and tightening residency permit criteria. That's certainly a course of action which would be expected to create much more unease in other parts of Europe; the furore over whether prioritising Single Market alignment in the UK's future relationship with the EU over an assumed preference for immigration restrictions that wasn't even on the relevant referendum ballot paper is a notable contrast. But I'd imagine there were aspects of the Swiss political psyche other than "maturity", "long term vision" or experience with referendums which made them relatively unenthusiastic about an impractically-high UBI proposal, high minimum holiday entitlement and supremacy of Swiss law over international law and relatively enthusiastic about banning minarets, allowing greater surveillance powers and [until remarkably recently in some cantons] restricting the franchise to men. Californians certainly don't have a particular shortage of referendums either.