Nah. You vote one time and that's it.
Opinions can change but there was a reason you voted before. Otherwise think before you vote.
That assumes users always vote with perfect attention and complete certainty, which is not realistic. Polls on suggestion threads are meant to reflect the community’s current opinion, not permanently lock in mistakes or rushed clicks (like happened above).
Preventing vote changes doesn't improve decision quality, it preserves inaccuracies. Allowing users to update their vote ensures the poll reflects actual, current consensus rather than outdated or accidental input.