I can't imagine not wanting to know enough to do basic repairs on the road/trail. With that, and a few tools, comes the ability to do most things. (I do recognize the world does not always agree with me, and others are OK with being befuddled by a rubbing brake mid-ride)

Concur with ItsJustMe's (and others') approach of a few tools and a book or website.

Honestly, if you have enough time to call around to a couple of shops and care enough about the $$ to bother, you probably ought to be leaning into doing your own work for the cost and time savings. Both are significant.

If you have neither the time nor the inclination to do your own work, then I don't for a second begrudge the rates that some are calling exorbitant. Pencil it out with all the dead time and overhead as some have started to -- you don't see many bike mechs driving a Lexus.