I appreciate your opinion, but I want to point out that our definitions of fairness and simplicity may vary. Much of scholarly work around elections systems strives to ground itself on particular formal criteria.
Comparative fairness is well documented. This graph is a good appromixation:
https://www.electionscience.org/wp-content/uploads/2018/12/c...
https://www.electionscience.org/library/approval-voting-vers...
Simplicity also accounts for election integrity concerns (ease of tabulation and auditing).
Do you have a formal definition for how you are using ‘fairness’?
Start with Arrow's Impossibility Theorem. You have the maths to better understand this stuff than me.
https://en.wikipedia.org/wiki/Arrow's_impossibility_theorem
https://www.math.wisc.edu/~meyer/math141/voting2.html
I have focused on election integrity. For me, arguing the relative merits ranked choice voting strategies is (unforgivable) bikeshedding and ultimately results in no action. Like getting stuck arguing 4.5x vs 4.75x better than FPTP while the world burns.
For election integrity, other real world concerns also must be factored. Like voter education, verifying the hardware & software, ease of tabulation & auditing, feasibility of doing a manual recount, etc.
In conclusion, Approval Voting is almost as fair as the ideal Score Voting but much easier to implement.