I feel like passion projects can be worth it. You’d want passion, and to attract people who want to work on cool stuff and do difficult or impossible things just because they’re hard or fun.

Let them do that without taxpayer money! If NASA announced, "We're looking for investors to revive our SR-71: for $10 million you get a sticker with your logo in the cockpit and for $50 million you can have a ride." I'm sure they'd have plenty of takers.

> attract people who want to work on cool stuff and do difficult or impossible things just because they’re hard or fun

Then make them work on fixing the healthcare. NASA is using its budget to keep 25 MiG-21 ariplanes fly worthy? It doesn't make any sense.

NASA isn't keeping 25 MIG-21 flying, Draken is, as a contractor providing dissimilar aircraft training to the US military (and other nations).