Thanks for your patience, I’ve now had a chance to really get into this and so hopefully I can answer pretty much all the queries posted here.
First, the CMP message should absolutely not be appearing multiple times a day. We made some changes last week to the list of partners we work with - which means we need to ask everyone on site to give cookie consent again. But that should only mean seeing it a maximum of once a day - not the multiple times that some folks are reporting. (Nb on Apple devices you may well have to re-consent every 24 hours - depending which sites you come to Mumsnet from. If you come to Mumsnet from a site that tracks you across devices (eg Facebook) Apple will delete your cookies within 24 hours and you'll have to re-consent when that happens. If, however, you come to Mumsnet directly or from a site that doesn’t track you across devices (eg you put Mumsnet directly into your browser) then Apple deletes your cookies after 7 days, and that's when you'll have to re-consent. You can read more here webkit.org/blog/8828/intelligent-tracking-prevention-2-2/)
We have asked Google whether they've made any changes at their end that would have caused multiple pop-ups but it does seem that reports of it appearing multiple times have stopped now? One reason may have been that you do have to give consent on each and every device you use, plus your preferences will not be remembered if you put your browser into private or incognito mode, and some browsers - eg Brave - blocks cookies and trackers by default, so it’s possible those things may be what caused the multiple pop-ups for some but if this is still happening or happens again please do let us know as it definitely shouldn't be happening.
One thing I can be absolutely clear on is that the reason why it keeps/kept appearing is not because we have some evil plan to beat you into submission with an annoying pop up until you accept all the cookies! As AdaColeman, Odile13, BertieBloopsMum and MashedSweetSpud (amongst others) have all pointed out on this thread some users have seen it multiple times even when they have clicked "accept all". If it is still showing it’s a cockup, rather than conspiracy.
Secondly - you can (effectively) turn everything off with one click. Clicking on the "Manage Consent" button (we’ve changed the wording on this to make it clearer - it was formerly "I want to know more') takes you to a page where all of the consent toggles are default off. By submitting that form you will block all vendors from using your data.
With regard to the legitimate interest toggles - these are on by default, and we can’t change that, as it’s set that way by Google. The reason Google has chosen to have then as default on is that under current regulations vendors who have legitimate reasons to process your data do not actually need to ask for your consent to do so. By setting these toggles to off you will notify vendors that you object to them processing your data but it won’t compel them to stop doing so, it’s only an indication of your preferences.
I do sympathise with those who are saying that when they click to check if their preferences have been saved they find that their preferences have been wiped. This is another irritating feature of the Google platform. When you access the link for a second time (from the "Privacy Settings" link, for example) it doesn't actually function as a "settings page" where you can see what you've said before. Instead it’s what’s known as a revocation link - so when you click it, it assumes you wish to revoke your previous selections and starts the process again - so it appears that your preferences haven’t been saved. But rest assured your preferences are definitely being saved, until you click the link for a second time.
All of which is to say that we're working with a sub-optimal platform here I'm afraid - we chose Google as a provider because, given they’re the world leaders in online advertising, we rather expected them to produce a decent product - we will certainly give Google this feedback and hopefully they’ll make improvements. Though everything is being done in accordance with the rules and your preferences are definitely being stored and acted upon, I agree it’s not a great user experience. So we will take a look at other platforms to see if there are better solutions and we will look at introducing a reject all cookies button to make it easier to do so in one fell swoop. Meantime we're going to do what we can to make all of this clearer around the site and in the wording of the pop up.
I do hope that’s reasonably clear - thanks very much for the feedback and of course let us know if you have further questions or problems.