Asking if they're necessary is missing the point. There should be 2 categories for people to think about here, macros that are useful and those that aren't.

For battle, most macros are actually counterproductive. The best macros for battle are the new ones for ground target aoes, other beneficial ones like embrace spamming, and /statusoff "Blood for Blood" for times you need it to be gone before a big hit. Anything related to anything on gcd other than those situations will slow you down.

Outside of battle classes go for it, though lag can mess em up.