I think this depends on how big the shop is. My husband is a shop manager for a school bus company. He has 12 years of experience working on diesel engines. So, he has some junior mechanics that do things like oil changes & headlights, preventative maintenance--to free up his time to do some of the office things like managing inventory & scheduling safety inspections. He still works on the buses, but specifically on the less-routine requests. (Not sure why the engine is making this noise. Not sure why we replaced the brakes and they're still not working. ) So he gets to do both!
If this is your eventual goal (owning your own shop), you should consider what are some initial steps you can take to get yourself ready? Some examples, do you already have some experience? Could you expand your experience to make yourself a more valuable, senior mechanic, to prepare you for the more difficult problems people will bring you as a shop owner. Auto technology is evolving. Are there ways you could get experience with electric or hybrid vehicles?
There's some "necessary evils" in any job--we can't all do our favorite tasks all day every day. I got a lot of advice along the lines of "do what you love and you'll never work a day in your life." That's not true. Even if you love it, there are days or specific tasks where you just don't want to do it. And that's OK. What's important is that those feelings are the exception not the rule. If they're nonexistent, then you might not be challenging yourself. (That might seem like a great deal now, but as you continue to work for the next few decades, it can get very disheartening to not have goals and challenges.)