When I said they have problems with "R", I was speaking from the perspective of this English language we use here at this board.

An ai response:

English "R" Sound:

Japanese speakers often have difficulty pronouncing words that begin with "R" because the "R" sound in Japanese is different from the English "R" sound. In Japanese, the "R" sound is more like a flap or a tap, similar to the "D" sound in English but produced further back in the mouth. This sound is not a true "R" as in English, but rather a sound that is somewhere between an "R" and an "L".

Therefore, when Japanese speakers attempt to pronounce English words that begin with "R", they often produce a sound that is closer to an "L" or a flap sound, which can make it challenging for them to accurately pronounce the English "R" sound.

Additionally, Japanese does not distinguish between "R" and "L" as separate phonemes, making it difficult for Japanese speakers to hear and produce the distinct "R" sound in English. This is compounded by the fact that in Japanese, the "R" sound is not rolled or trilled as it is in some other languages.

Research indicates that even after extensive training, Japanese speakers may still struggle to distinguish and produce the English "R" sound accurately. However, with focused training, some improvement can be observed.

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Of course, this is said of many Asian first-tongues generally, not just Japanese. Looking at the internet, I can see people jumping at the PC opportunity to be woke, announcing that being of Asian descent "does NOT" make someone have difficulty with the English pronunciations of the letters R or L.

https://i.imgur.com/O9tdPgb.gif

Naturally, we're talking about first languages, not racial heritage, and the sterotype exists exactly because it is so common.
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All about Engrish:
https://knowyourmeme.com/memes/engrish
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https://images3.memedroid.com/images/UPLOADED815/662a28c1c432a.webp

I would reference a post I made here, recalling when a Japanese man stopped me in a hotel lobby, asking me where is the west room. I informed him I had seen a large East Room down the hall, but no West Room. When he expressed it with more urgency, I suddenly understood what he meant, and he was soon very relieved that I could direct him.