Sorry to read of your disappointing experience. It does raise some questions for sure.
I'm actively going out of my way to but anything but Chinese now days. Apart from such mixed qualities, many other manufacturing companies are moving their operations out of China over the past couple of years. It seems the Corona Virus has given the world it's long overdue wake up call that putting all our eggs in one basket isn't smart. I feel by buying goods made in other countries is doing my small bit to help this situation.
Last Jack I bought was a Bahco, made in Sweden. Pleasantly, it was no dearer than the Chinese Jack it replaced. The Chinese item did work well, but only lasted about 2 years before the hydraulics gave up. I figured I could repair it myself, on disassembling it, I found that the fasteners were neither metric or imperial and the seals within were totally oddball, that was when I gave up on it as a bad joke. I've had the Bahco now about 6 or 7 years, still going as well as the day I bought it. It also has a 2 stage pump so is much nicer to use than the Chinese item.
I've found it's definitely worth spending a bit more time seeking out alternatives. While the Jack here was the same money, often what I buy is dearer, but not by a lot, however the quality has been chalk and cheese.
Couldn't agree more