I'm going to assume you mean atime specifically, and not olcuc or anything else (you would have a hard time arguing for that one).
To remove old cruft, a good start is quarantine. Simply don't implement atime in new file systems (btrfs); people who need it for their business-critical fingerd can run UFS or ext2 or something else. The important part is that we don't let use of a bad feature to spread, since that is only going to make it harder to get rid of.
Instead of making code worse for everyone for the (dubious) benefit of a vocal minority of cavemen, deal with the problem head-on. Give them a chance to adapt - help them all you can - but set a firm date for when the coddling stops.