chore: deprecate unused messages instead of removing them

[julienrbrt]

Description

-> PR against main #14597

See #14591 (comment)
It is not clear for me what is the consensus. If we want to re-add it, here is a PR for it.
Otherwise, we can just leave it as it.

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[tac0turtle]

do we still want this?

[amaury1093]

I would say this is still useful, for those still using v1beta1