Those bots have always been around, sometimes more and sometimes less visible depending on what creative tactics the bot programmers have come up with and what countermeasures SE has devised (the death trap under the entrance to the Waking Sands will always be one of my favorites even if bots seem to now have a way to avoid it).

They usually get banned by the thousands each week (see the weekly "Actions Taken Against In-Game RMT & Other Illicit Activities" notice) and each week the bot operators create thousands more.

There's no quick and simple solution to the problem no matter how much some players want to believe there is.