The robots.txt is for well behaved bots. I already deployed that list quite some time back but it didn't help, because the problem are the not well behaved bots.

Iocane should be showing hidden links that only bots can see, and leading then into a maze of gibberish. It has other features too, but the core function is to keep them busy on easy to serve pages that poison their training and are inexpensive for your site to serve (as opposed to the lemmy pages, that have expensive database calls on every page load).