Should’ve required something like a 60% minimum, though they’d just have kept calling for the same vote every year.

This discussion came up back around Brexit.

While I can understand an argument in favor of stability -- you don't want to sit at 50% and have things waver back and forth -- there are a couple issues.

First, for better or for worse, this is not really the international convention. In the referendums I've dug up for independence, the norm is plurality of votes. This isn't quite independence, but it's probably most analogous to it, especially given that one expects ongoing integration.

Second, it seems to me that to bias towards the status quo, one would have also needed to have also met that bar to join. In fact, there was no referendum at the time of joining, an issue which had its own controversy. If a 60% supermajority is required to leave, it seems to me that the same should be true of joining.