I'm in the group that learned to sharpen freehand then moved to guided systems.
For at least 25-30 years I never had anything other that a few stones and a bunch of knives. I had no difficulty putting on a clean and even bevel that was sharp enough to tree-top hair. I know that I 'can' sharpen freehand.
As a youngster I spent a lot of time sleeping on the ground. As an adult in Asia I spent a lot of time sleeping on the floor. I know that I 'can' sleep on the ground. I also know I 'prefer' to sleep in a bed.
My goal is a perfectly (and quickly) sharpened knife, not a contest with myself. I use guided systems now, and have for the past 25-30 years.
I can still freehand if 'needed,' but I never seem to need...
I keep a Sharpmaker set up in the kitchen for weekly touch-ups
I use a DMT Aligner for portability and for sharpening at times when I don't have a table to use
I use EdgePro 2-3 times a year to sharpen all my 'user' knives
Sharpmaker -fastest to set up and easiest to learn to use, but limited in angle choice
RazorEdge - smallest, adjustable, but wears out after several years usage, can be used with stones or sandpaper
DMT Aligner - cheapest, several different angles, lightest weight (for backpacking) can be used with stones or sandpaper
GATCO/Lansky - adjustable angles but must be used with their own stones
EdgePro - the Benchmark by which most others are judged. Infinitely adjustable, easy to learn, good choice of stones, but expensive
WickedEdge - very expensive, a bit more difficult to use on very long blades, but excellent results
Obviously there are many others, but this may give you a general idea.
Stitchawl