an entry level camera at times is a bit like the idea of a 'simplified guitar' with just the Low E, D and High E strings
I think the analogy is stretching....

A guitar with three strings is unusable, or it's an out of tune Balalaika. Using an entry level camera that doesn't work properly would be closer to a guitar with strings missing.
In answer to the OP (and not really knowing what they mean by amateur): Without a doubt the biggest barrier to entry I discovered running courses for adults was the bewildering array of buttons, settings, and dials along with badly designed UIs in camera menu systems. Almost all cameras could perform normally, but making that happen was an exercise in frustration for many. Smaller compacts with fiddly buttons and overly sensitive touch screens compounded the problem.
Teaching the basics of shutter, aperture and ISO was easy. People got it. The fear started when they tried to make their cameras do what they wanted. I remember showing them the Fuji X-T1 I had at the time, and as one they all commented on the fact that it was so easy to operate. The thing is, it's easy to operate when you know what these things are. It's gibberish to someone who hasn't a clue. Practise, perseverance and experience is the answer. Those who persevere with their menu buttons soon become proficient in diving into the settings. Some people though, prefer an easier camera to use because they've forgotten it after 5 minutes - especially turning on and off of exposure preview - I lost hours Googling that one for various camera manufacturers.
My R6 is set up just how I like it. I can operate it quickly and apart from forgetting which button turns face detection on/off and confusing it with the button for focus switching, I'm pretty quick with it. The rest of my stuff is film, and that's just super easy to use apart from the late 90s/early noughties automatic SLRs that are just as confusing to use.
The only camera I got rid of pretty quickly was a Panasonic TZ100 (I think?) Small compact designed for right eye dominant photographers with a lot of reliance on a touch screen that my nose would play havoc with every time I had the camera to my face. Had to turn the touch screen off and then fight with a [really bad IMO] menu system to do what I wanted.
Phew, that ended up being longer than I planned.