On a similar and relevant note, It probably annoys those who have some music theory when they deal with other musicians who don't understand key signatures. Eg, “The chords go E A B C#m then Gbm” enharmonics, they musically-sound correct, yes, but technically not named correctly.
I can live with this in the same way that i understand everybody has their own way of understanding things and often we adjust our own language to communicate with others who we know understand differently, a bit like using a local dialect.
Dealing with the younger generation the sharp sign now gets referred to as the “hash tag”, something that didn't exist when i started learning but i find myself (reluctantly) having to call it that to connect with young players.
I suppose a sharp sign is more distinct and available in a regular character set than a flat which is often taken as a letter “b” and perhaps why it has been used more?