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The reality is that anything we fly into space is already generations behind the equivalent earth technology."
There are many reasons for that. For one thing, the environment that it has to operate in is...poor. The "best of breed", most modern technology typically doesn't like that sort of thing. The technology in your automobile's engine compartment is also typically generations behind, as is the stuff in your toaster (for slightly different reasons).
Second, the technology of the manned program (and the same argument applies to a lesser extent to the unmanned program) is "man-rated"---it's specifically tested to ensure that it won't fail in some spectacular fashion and kill everyone. That is expensive, and takes a lot of time. One way to make that cheaper is to maintain a pedigree; what you fly today flew yesterday, or is based on something that you flew yesterday.
And then, of course, at current effort levels, building a new launch platform is mostly a non-starter. So, you might as well go with what's already working.
"Spaceflight has contributed very, very little technology to earth."
You need to keep a distinction in mind: manned vs unmanned. Unmanned flights are plenty competitive in terms of basic research.
Further, many people, before the Internet Boom, got into science and technology because of the manned spaceflight program. To an extent, some of those that went into spaceflight-specific programs were lied to. But still, they have made some contributions, somewhere.