I have not seen that on any browser, including Opera, and including when I disable the Opera Ad blocker and Tracker protection.
I guess you don't see them because of your geolocation.
EU has a law mandating from any websites (no mater where the website is hosted) to ask for the user's consent before using cookies. My guess is, the new customized-ads company is complying with the EU regulations, so it is serving the cookie agreement request to any EU user.
The consent request is asking to share the user's data/behaviour for the next 13 months with about 1700+ other companies. It also tells you that they will share anyway
some/partial data about the users (no mater if you refuse or not), just that the user has the right to complain.

Tracking of the individual users is made under the pretext of serving them "personalized" adds, based on what they do on EEVblog. If you ask me, that seems very intrusive. I trust you/EEVblog, but I don't trust the surveillance from thousands of other third party companies.
This is a copy-paste of the request I receive when turning off the ad blocker:
We value your privacy
We and our partners
store and/or access information on a device, such as cookies and process personal data, such as unique identifiers and standard information sent by a device for personalised advertising and content, advertising and content measurement, audience research and services development. With your permission we and our partners may use precise geolocation data and identification through device scanning. You may click to consent to our and our 1731 partners’ processing as described above. Alternatively you may click to refuse to consent or access more detailed information and change your preferences before consenting. Please note that some processing of your personal data may not require your consent, but you have a right to object to such processing. Your preferences will apply to this website only and will be stored in IABGPP_HDR_GppString cookie for 13 months. You can change your preferences or withdraw your consent at any time by returning to this site and clicking the "Privacy" button at the bottom of the webpage.
Please note that this website/app uses one or more Google services and may gather and store information including but not limited to your visit or usage behaviour. You may click to grant or deny consent to Google and its third-party tags to use your data for below specified purposes in below Google consent section.
Then, there is another window where you can scroll through the list of those 1700+ companies, and you can turn each on/off if you want, or admit/reject all.
Since outside of EU there is no law mandating the user consent, I guess everybody visiting from outside EU is not informed about their data being shared with 1700 other companies, and non-EU users are just tacitly enrolled to share their data (indirectly enrolled by the customized ads-placing company, not by EEVblog), but I didn't check how it really is, just a guess.
You should receive these consent requests, too, if you browse from EU (try browsing the forum through a VPN, with the exit point anywhere in EU, also delete your cookies first, because you might have already been enrolled while you were visiting the EEVblog forum from Australia).