(Going from memory here)

No, it's possible that there's a single gene that would do it, meaning a single mutation would enable it. But that's not what happened here. Instead, there were multiple genes involved, with some of the necessary mutations occurring long before the other.

I guess you could say that evolution is a sort of a paradox of heaps.[0]

Somewhere inside an organism must exist the means to evolve into another creature otherwise if it didn't it couldn't.

My layman's interpretation of this experiment is that the results characterize the process of evolution of a genome adapting to an environment overtime until novel phenotypes develop.

I find it awe inspiring to think about every single organism that ever lived and the entire surface of the planet has been defined by the first organism that came into existence and the particular chemical makeup of the first location where that occurred.

[0] https://en.wikipedia.org/wiki/Sorites_paradox