Handy?
Yes, that's what they want you to think. Make it look respectable, doesn't it?
"Oh dear me, no, we don't need laws to control us - self-regulation is the answer - look, we've even set up a handy site where people who don't want it can opt out."
Like anything set up by the advertising industry themselves, it is for their benefit, not yours - with obvious discontent in Brussels about the current state of affairs, they are getting a little worried that their activities might be restricted, and will just use this sort of "helpful" site to demonstrate that they are nice responsible people, so there's really no need for anyone other than themselves to control what they get up to.
On the "Human to Vermin" scale, they sit below estate agents and only just above Idi Amin - they are a bunch of avaricious scum who cannot be trusted in any way, and you should not have to go to any site and opt out anyway - all behavioural advertising systems should be "OPT-IN", with a very clear message about what is actually going on, not a load of bull about "improving your internet experience", and not "opt-out".