But given the general security situation on Windows, it would be really nice to have, for example, the browser strongly isolated from the rest of the system.
The idea of using virtualization to enforce stronger isolation between different parts of the system seem like a good one, and it does not appear to be that non-obvious (of course, in hindsight so many things do).
I think in the context of the entire sentence it's clear that the choice of words is correct as written.
I mean that in retrospect the idea is obvious, as in, "why did I not think of that".
Of course, in computers and technology there are many, many ideas that appear obvious in retrospect but were still hard to arrive at.