What I've personally noticed is not so much bots vanishing but shifting fields. Ever since the LL speaking out about it but ALSO announcing the app I've seen a HUGE upswing of market board retainers who undercut your listed goods by 1 gil pretty much as clockwork down to the second. Before I was making a decent amount of money from the marketboards but with the syndication AND the upswing in MB-bots I haven't sold an item for months