My two cents: I can easily recall when mainstream astronomy considered
searching for exoplanets as too difficult and not a top priority. Some even
questioned if other planets even existed in any significant amounts.

That certainly changed in 1992 and especially in 1995, didn't it?

The same will happen with astrobiology when the first discovery is made.
But we can't find them if we don't search for them, can we?

What Griffin Thinks - and the Academy Says - About Astrobiology

http://www.nasawatch.com/archives/2006/05/what_griffin_th.html

Outspoken: Mike Griffin on the NASA budget, Nature: "Deep cuts to NASA
astrobiology - Griffin:

"I did think astrobiology was less important than traditional space science. It
had less intrinsic subject matter to it, and was less advanced. If the community
rises up and says it should be funded, we'll rethink it."

NASA Lacks Resources Needed to Sustain Vigorous Science Program, National
Academy of Sciences:

"The decadal surveys for astrophysics and for solar system exploration both
embraced astrobiology as a key component of their programs, with the questions
encompassed by astrobiology serving as overarching themes for the programs
as a whole."