Maybe I worded that incorrectly. What I mean is that you would be fine giving a kid a brushed quadcopter without worrying that they're going to filet themselves (for the most part. Yeah they could cut themselves but the damage would be order of magnitude less than with a brushless). Giving a brushless quadcopter to a kid without any instruction would be totally irresponsible. They're still toys yeah but can be pretty dangerous if you're careless.
I'm trying to understand the difference between the two types of motors and found this: https://lifehacker.com/are-brushless-cordless-tools-worth-th...
They talk about the more efficient battery use but not the added power or danger of brushless motors. Can you find a link that does explain it?
In short brushless motors are a 3 phase ac induction motor for the ones used in quads.
Brushed motors are the classic motors that you may have played with as a kid, put in a dc current and they spin.
Brushless motors are much much much more powerful and essentially only wear out due to heat, or bearings failing.
Brushed motors can be damaged by stalling, heat, etc and much more easily.
The important part that the above poster was trying to make is that a brushed motor, any size that would be used on a retail drone/quad/ etc might spin a prop with enough force to cut..... maybe even need a stitch or two but unlikely that bad.
Whereas the brushless motors used in even small quads would most certainly need stitches, and maybe even sever a finger.