Did some searching, apparently it can be variable in taste due to sea urchin diet, freshness, and preparation. There are commercially prepared pastes that aren’t very palatable.

The urchin I had was really expensive and was a special that was rarely available. This sushi place had very good stuff, you could also order freshly grated wasabi from imported Japanese roots (I totally recommend).

Probably similar to canned crab vs fresh crab. Stuff in the can is terrible and I don’t know how people eat it.