The only OECD country that can beat the US in killings by law enforcement per capita is Colombia with 33.1 and 34.1 killings per 10 million people a year respectively (according to wikipedia). I think the person you replied to were right in saying that “So if I’m interacting with law enforcement but in an industrialized nation that is not the US, I’m likely better off by far”. Granted, Mexico isn’t much better off either, but beyond that the numbers start to go down.
Police brutality is definitely not a uniquely US thing, but it is a lot more prevalent there than in comparable countries.