I don't think it's safe to say that at all. Where do we get this foolish notion that a job involves only one specialized kind of activity?
You wouldn't tell a software engineer that their only job is to crank out code. That's actually a recipe for either 1) an absolute savant, or 2) a severely career-limited engineer. Engineers need to plan, estimate, document, test, troubleshoot, help recruit, and be technical leaders for all sorts of random things that come their way. We often deride that stuff as "admin work" that keeps us from our true calling – but let's be honest, that actually is part of the job description.
Similarly, it would be foolish to tell a professor that their only job is to sit in front of the classroom and teach. They should be expected to spend time improving their pedagogy, attracting students to their program, being a champion and mentor for students, spending some time in public outreach, and otherwise helping to drive their department's curriculum and agenda so it will flourish. At a research university like Stanford, they will be expected to spend time attracting research and research funding as well. Professors may bristle at having to do all that, and they can't do all of that alone – but again, it's part of the job description, and there's good reason why they're being tapped to do it! You really can't expect an admin to drive the research agenda of your department, for example.
So, where does your statement come from? How do you define "admin work"? Are you a teacher that feels like you're tapped to do stuff you shouldn't be doing? Are you really sure that's work that should be delegated?