Your experience matches mine- I only ever heard "trickle down economics" used by people on the left making mocking, derisive commentary about Reagan and neocon politics.

Then someone pointed out to me that my entire affluent, privileged, comfortable life is due to trickle down economics. In the last 15 years, I've had high salaries paid by various money-losing startups, financed by rich people investing in VC funds. Now I'm a millionaire, entirely as a transfer of wealth from the rich. I haven't had a job where my salary was realistically paid by customer money/business revenue since before 2010 or where any of the VCs ever made their investment back.

I don't know if there's any lesson to learn from that or if it's just funny or ironic, but it is kinda entertaining to me to realize the entire Venture Capital backed economy can be seen as trickle-down economics "working".