You’re not entirely wrong. Any conversation with them would inevitably drift off into the weirdest tangents, and they would happily continue their side of the conversation, even if the person to whom they were speaking had to walk away or start doing another task. They weren’t bad at the job, but they weren’t great either, and they were consistently odd, and not in a fun quirky way.
What’s a space cadet in this context?
Someone too focused on being an astronaut to pay any attention to the work that needs to be done at their normal job
You’re not entirely wrong. Any conversation with them would inevitably drift off into the weirdest tangents, and they would happily continue their side of the conversation, even if the person to whom they were speaking had to walk away or start doing another task. They weren’t bad at the job, but they weren’t great either, and they were consistently odd, and not in a fun quirky way.