I remember it would hit 100k sometimes even back on '06. It's definitely declining.
Yeah, because there were no bots back then, right?

I remember walking by Willows next to Draynor (the ones next to the farm house) on any F2P world and seeing the MASSIVE herds of bots. That's just 1 example. Another obvious one would be all the essence miners.
When I was training RC (got 99 back when nats were a healthy 300 GP each), whenever I bought essence in Fally, the person with the best price was obviously a bot/gold farmer. And they always had mills of essence to sell.
The people that couldn't be bothered because they either couldn't get a good training spot for a skill, or couldn't be bothered because they had to sell things for too low, will be finding skilling (and playing RS) worthwhile again due to (almost) no bots.
There are also the people that were unmotivated to level because of all the botters getting 'easy XP' while they spend their time on it, that are now motivated to level again because of most bots being gone.
Me for example, before the nuke I was close to only needing 1 99 (Hunter) to become maxed. If the nuke hadn't happened, I wouldn't of been able to get myself to bother with Hunt due to all the bots at various spots. But instead, the nuke did happen, and I will be 99 Hunt tomorrow and get to design my max cape tomorrow night.