Before Go Modules it was a best practice, Go Module made it a requirement - and that’s where my whole issue with Go Modules is at this point.
Most users use some kind of third party dependency which understands that a move from v1.5.x to v1.6.x is safe, as no backwards incompatibilities should exist - and that the same does not apply to a move v2.0.x. This is why we are tagging it as v2.0.0, regardless of Go Modules support.
That said, we are facing a similar issue with v2.1.0 which will be API compatible with v2.0.0 but the data format will change forcing users to backup and restore their database.
Maybe we should make that also a non backwards compatible change, and therefore release a v3.0.0 instead. I’m sincerely curious, what would you do in this case, @adg?