In regards to bots or real players using macros or however they happen to do it. I would suggest CCP employ a “report spam” mechanic.
Whether it’s the Jita local or a recruitment channel or a local chat with a fleet full of dummies passing through, chat windows flooded with junk are a pain.
What about being able to flag a player as a spammer and the response would be to increase the time delay for which they can post again.
A bot in a recruitment channel could advertise an ad and repeat the same or altered message each five minutes as they do now every day all day. I literally took a break for a couple of years from EvE just to come back and see the same spammers still in my block list posting the same things. Labelled as a spammer this might increase to 6, 7, 8 minutes etc.
This would keep macro spam wayyyyy down and almost entirely defeat bots.
Another example could be the Burn Jita event wherein a player is killed but to sour things the killers spam the chat over and over and over again with the killmail. Labelled as spammers they would quickly lose the ability to spam and even chat without serious delays.
I saw a player complaint in this forum where the offender spammed NIGGERSNIGGERSNIGGERS over and over and over again… I have seen the same thing many times? But labelled as a spammer that would quickly die out.
The spammer would have their post delay reduced, and then removed after x time to be determined.