Probably the are navegatin in new and as soon as they see non-english they downvote. These people doesn't even have a single post in other than english,
You vastly underestimate the idiocy and childishness of Americans. I've seen people comment things like "use English, this is a US website", "go to another site for your own country if you want to use anything other than English", etc. even though the posts were in communities/subs specific for the language the post was in.
This has always been a thing online.
Many Americans are so dumb they think they are the vast majority on any website, and everything should be via their rules and ways. And there are several other things that seemingly only Americans are dumb enough to do and/or to not understand, things like timezones (even though they have several within their country), that the vast majority of the world uses Metric, that not every country has the same products or services, that their subjective experience of anything is in fact subjective, etc. I could go on for several more paragraphs with things like this.
Fact: the US uses the metric system for decades (maybe closer to a century?). All federal contracts in the US must be in metric. Its not the same at the State level, and its not mandated for private businesses--unless they're working for the federal government.
Also every US American is taught metric in schools.