This is actually the least defensible claim there. I posted this in the comments:
"Every Voting System is Manipulable" is an exaggeration of the implications of strategic voting. Yes, the Gibbard–Satterthwaite theorem proves that a dishonest vote could profitably exist in any system, however there are already systems where intentionally doing so requires the voter to:
1) Have perfect (or near-perfect) information about exactly how everyone else is voting, and
2) Solve an NP-hard math problem.
When breaking the vote requires more knowledge than any politician has, and more computing power than breaking the cryptography of all the world's banks, I'd say it's not particularly manipulable.
Could you go over the good solutions then? I have always heard there are about 4-5 "good but complicated" systems, none of which are easily shown to be best due to strategic voting and haven't seen clear "we should do this one because it beats all those for sure" type recommendations.
"Every Voting System is Manipulable" is an exaggeration of the implications of strategic voting. Yes, the Gibbard–Satterthwaite theorem proves that a dishonest vote could profitably exist in any system, however there are already systems where intentionally doing so requires the voter to: 1) Have perfect (or near-perfect) information about exactly how everyone else is voting, and 2) Solve an NP-hard math problem.
When breaking the vote requires more knowledge than any politician has, and more computing power than breaking the cryptography of all the world's banks, I'd say it's not particularly manipulable.