10% efficient, without working fluids or moving parts, can be epicly more practical than 300% with those things. In very small or hard to reach places, peltiers are often only real option.

Yeah, pretty much. I haven't seen a compressor-based cooler that's a few cm across. But it's not something that will replace AC, fridges, or freezers, which is where they get hyped in popular media. It's a niche technology for niche applications.