> whereas many Americans will understand it to mean that you’re not good
I haven't found that to be true. Tooting your own horn is generally looked upon as impolite in many circles. It's pretty common for someone who is outstanding at something to say "yeah, not bad".
And in a very meta way, it can be seen as a flex. Someone who is undeniably the best at something can say "yeah, I'm not bad" with a smirk to show that yeah, they know they are very good.
Now there are some circles in the US where bragging is common - banking, VC, hell even tech. But that's not America.
I haven't found that to be true. Tooting your own horn is generally looked upon as impolite in many circles. It's pretty common for someone who is outstanding at something to say "yeah, not bad".
And in a very meta way, it can be seen as a flex. Someone who is undeniably the best at something can say "yeah, I'm not bad" with a smirk to show that yeah, they know they are very good.
Now there are some circles in the US where bragging is common - banking, VC, hell even tech. But that's not America.