Just making a simple point
Unexpected success is a likely, or unlikely, as unexpected failure. I am suspicious of the motives of those who constantly push the latter (nobody here.)
If we want to see serendipity in these areas, we need to cultivate those factors in society that encourage it, and this includes a decentralized approach to research and development and the freedom to succeed.
A "Manhattan Project/Apollo" approach usually only works if you know exactly what you want going in.