Does somebody claim it was?

They don’t advertise against travel to US (yet). If they did, it would read like this:

Utenriksdepartementet fraråder alle reiser til Myanmar.

The Ministry of Foreign Affairs advises against all travel to Myanmar.

Regjeringen.no – reiseinfo Myanmar

A travel warning also is very explicitly indicated as a “warning”, e.g. here:

Vor Reisen nach Myanmar wird gewarnt.

Deutschen Staatsangehörigen wird empfohlen, das Land zu verlassen.

People are warned against travelling to Myanmar.

German nationals are advised to leave the country.

Auswaertiges-Amt.de – Reise & Sicherheit: Myanmar

Not really a travel warning, but a hint:

Når du skal søke om ESTA eller visum til USA, er det to kjønnsbetegnelser å velge imellom: Mann eller kvinne. USA anerkjenner kun søkerens kjønn ved fødselen. Reisende hvis nåværende kjønn avviker fra kjønnet ved fødselen, anbefales å kontakte den amerikanske ambassaden før reisen for råd og veiledning.

When you apply for an ESTA or visa to the USA, there are two gender designations to choose from: Male or Female. The US only recognises the applicant’s sex at birth. Travellers whose current gender differs from their gender at birth are advised to contact the US Embassy prior to travel for advice and guidance.

Regjeringen.no – reiseinfo USA

Then they opened the can and tasted the fish…

Epic. I don’t know if Surströmming can actually spoil.

Some years ago, surströmming was actually used to scare away the voles around the king’s library in Stockholm.

Surströmming based area denial. At least it works against voles.

I’ve always thought, this was a German thing.