The reason may be less that the LW community believes voting is rational...but that the LW community already understands that voting IS irrational, and the LW community is just reacting negatively to having the same idea be brought up again.

I understand you provided some solutions to try and make voting 'rational', though, however, I do disagree with the idea that #3 and #4 would actually work. Voting only becomes rational when your vote does sways an issue, and not only is this chance incredibly small, but it would likely provoke an automatic recount, meaning your vote is again proven useless.

Providing one extra vote to your side when your side is already is winning/losing is inherently irrational (at least in terms of swaying policy, not signaling views).