alt Hacker NewsRelated: https://pkg.go.dev/crypto/subtle#WithDataIndependentTiming (added in 1.25)
And an in-progress proposal to make these various "bubble" functions have consistent semantics: https://github.com/golang/go/issues/76477
(As an aside, the linked blog series is great, but if you're interested in new Go features, I've found it really helpful to also subscribe to https://go.dev/issue/33502 to get the weekly proposal updates straight from the source. Reading the debates on some of these proposals provides a huge level of insight into the evolution of Go.)
I have to wonder if we need, say, a special "secret data" type (or modifier) that has the semantics of both crypto/subtle and runtime/secret. That is to say, comparison operators are always constant-time, functions holding the data zero it out immediately, GC immediately zeroes and deallocs secret heap allocations, etc.
I mean, if you're worried about ensuring data gets zeroed out, you probably also don't want to leak it via side channels, either.