Even I just came to my senses and found out about this.
So the use of capital letters will depend on the context.
So far, I just write about what I wrote. Commonly, only used upper case for the starter of a sentence and then will be in lower case, or even I don't pay attention anymore to the use of B in upper or lower case. New for me.

But, if most people don't know about this, will it really influence the meaning of the word "Bitcoin/bitcoin"?