Trickle down is based on the mistaken assumption that rich people will spend all their money in the local community. When often they don't spend their money at all and just save it, and when they do spend it it's on expensive yachts in Monaco. They're not contributing to the economy in which they live.

The millionaire class were delighted when they saw this idiotic take and pushed its narrative knowing full well that it would be to their advantage.

I don't think I've ever heard it called a trickle up economics but yeah, it would work because most people have no choice but to spend locally. If I got some money from the government I would buy food in the local supermarket or get my house redecorated by a local tradesman.

Various tests of UBI have shown that it doesn't really increase laziness beyond the base level it was already at, after all it's mostly the rich who are lazy anyway, as they're the only ones who have the resources. All it really happens is people want more time off work because they can subsidise their income with UBI, but that is an expected and desired outcome as it means more people will be employed to cover the difference which gets more people in work and therefore paying taxes.

To give a quick highlight, because this case is often politicized and misrepresented:

The plaintiff, Stella Liebeck (1912–2004), a 79-year-old woman, purchased hot coffee from a McDonald's restaurant, accidentally spilled it in her lap, and suffered third-degree burns in her pelvic region. She was hospitalized for eight days while undergoing skin grafting, followed by two years of medical treatment. [...]

Liebeck's attorneys argued that, at 180–190 °F (82–88 °C), McDonald's coffee was defective, and more likely to cause serious injury than coffee served at any other establishment.

So, the lawsuit never demanded McDonald's to put a warning that you're not supposed to spill hot coffee on yourself. It argued that it's an unnecessary safety hazard, because the coffee was served at hazardous temperatures.
No matter how many warnings you put down, it can happen that someone spills coffee on themselves and they shouldn't need to be hospitalized from that.