I'm not going to lie, somewhat immediately and on a large scale since about 6 months into the release of the 2007 game, Jagex has really increased their effectiveness against bots in a variety of different methods like this. Bots used to kill green dragons with whips until they were 200m exp in all combats. That's 200m exp in attack, strength, defence, hp, all against green dragons, netting well over $1,000 per bot (I did the calculations at one point with the gold price at the time and estimations).
Jagex was somewhat ineffective at controlling bots and RWT from launch until 2005, uselessly ineffective, but still harsh with punishments from 2005-2008, nonexistent with punishments and completely ineffective from ~2009 to EoC's release in 2012 (minus the bot nuke which slowed down bots for about ~14 days to 3 months depending on the bot).
The thing is even more clever, inventive, effective suggestions like relocating bots to bot watching worlds, etc, were suggested all during these periods, and none of them were ever implemented for reasons unknown. If it was because bots brought in too much revenue to eliminate them, they could have done it gradually and adjusted their budget accordingly, or in steps with propaganda hyping the progress against them. Instead, they just let bots dominate the game mercilessly with no lube for an entire decade and a half before doing anything about them, it really made no sense.