That's because trickle-down does work to some extent (which isn't to say it's not still a socially regressive economic idea). A larger share of the global economy going to someone in your town raises all boats.

But in towns where parent's trade-exported jobs predominated, there's only pain without the benefit. Hence the resentment of the policy.

Which is good. People getting pissed off about that and making political choices based on that fact should be happening due to the fact that we haven't allocated the increased wealth due to trade around fairly.

... Honestly, we're essentially running knowledge/tech trickle-down economic policies now. In that if you aren't one of that class, then hopefully some of that wealth might get down to you... eventually...