Mathematics is organically grown but reinvented every few years or so. Look at a mathematics paper from 50 years ago. Look at one now. Look at one 100 years ago.
Mathematicians aren't dumb. There's some element of tradition (that's a small part of the reason why many mathematicians prefer chalkboards to whiteboards) but most of the reason we use the notation we use is because it's the best way anyone has ever found to express rigorous, technical, creative, abstract thought cleanly and efficiently. Mathematicians routinely do completely /new/ work which requires us to invent entirely new notation out of wholecloth on the spot. The techniques we use are suited to this need. When we find something that's better, we use it. There isn't anything better yet.
Mathematicians aren't dumb. There's some element of tradition (that's a small part of the reason why many mathematicians prefer chalkboards to whiteboards) but most of the reason we use the notation we use is because it's the best way anyone has ever found to express rigorous, technical, creative, abstract thought cleanly and efficiently. Mathematicians routinely do completely /new/ work which requires us to invent entirely new notation out of wholecloth on the spot. The techniques we use are suited to this need. When we find something that's better, we use it. There isn't anything better yet.