The field is much older, MIRI is ~20 years old. Look up Eliezer Yudkowsky.

Eliezer Yudkowsky is not a scientist. He made a popular Harry Potter fanfiction series and a "rationality" blog-community that attracts "human biological diversity" enthusiasts.

Yes, he's the exact reason people are distrustful. He's a crank who learned about reward hacking and made a new religious movement out of it, pretending it's a world-ending issue and deliberately avoiding much more serious issues like the concentration of power. Typical cult leader and manipulator, and his disciples in charge of major AI shops aren't any better.

The field was purely theoretical 20 years ago, and Yudkowsky is pretty much the dictionary definition of "not accredited"