I am from the UK, and have always read phrases like "anyone who does this thing will be frowned upon" as ominous understatements portending heavy administrative action against violators.
For example, I recently interpreted a mod saying:
Further attempts to [perform some action] will be frowned upon
...to be a threat in "mod voice" of potential mod action against anyone who dared perform the described action.
However, a Canadian argued that they had not interpreted it in this way at all.
Is this a regional variation?
If so, might it be an intensifier/mitigator difference, like "quite" is usually an intensifier in the UK intensifier, but a mitigator in the US? Someone "quite tired" in the UK is aching for sleep, but in the US would likely just welcome a sit down.
That is, if someone in power says this phrase in, say, Canada, is the implication ever that you will "[merely] be frowned upon [and nothing more]", rather than "be frowned upon [and subject to the speaker's wrath]"?