I do prototyping for a living and ... I definitely do "X in 1/100th lines of code" regularly.

It's exciting, liberating... but it's a lie. What I do is to get the CORE of the idea so that I fully understand it. It's really nice because I get a LOT of millage very quickly... but it's also brittle, very brittle.

My experience is that most projects are 100x bigger than the idea they embody because the "real World" is damn messy. There are always radically more edge cases than the main idea enables. At some point you have to draw a line but the furthest away you draw the line, the more code you need to do it.

So... you are right to have mixed feeling, the tiny version is only valuable to get the point but it's not something one can actually use in production.