Open-source biotechnology

Quite so. Note that there *are* modular components in biology: things like
the Hox genes are conserved because so much other stuff depends on them
that if they change, the organism dies. But conserved components like this
are often little more than genetic switches, at most generating protein
that binds to regulatory regions of the DNA: the things that actually do
the *work* are rarely so conserved. (Sometimes they are, but even truly
ancient and insanely well-conserved things like hsp83 occasionally
mutate.)

More generally: conserved stuff has lots of stuff depending on it, so is
often hard to use in isolation; non-conserved stuff often depends upon
conserved stuff, so is often hard to use in isolation.