I don't really understand whether writing B and b in bitcoin will refer to the difference in meaning between the two, because according to what I know capital letters are usually used when writing at the beginning of sentences and capital letters are also often used to write abbreviations or acronyms, such as when writing abbreviations from bitcoins (BTC).
In general, it's true like you said letters B and b, there is no difference, only the letters are the same but the placement in different sentences, but in my opinion, the letter B only symbolizes bitcoin. By looking at only the letter B, people will immediately know that what is meant by B is bitcoin, for example. we see a symbol like this $ directly that is pictured in our heads dollar then that's how it is if we see the letter B.
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