Actually there is no such thing as a class action here, instead certain organisations are allowed to bring a community claim on behalf of consumers, for example such claims have been brought against water companies for dumping sewage in rivers and there are others for bad practices.
We also have a regulators who form part of a network of regulators all over Europe and they have the power to fine huge amounts with no Court involved. Companies can appeal but they are simply stalling, the decisions do not get overturned or reduced.
For example I rang the customer services of one company, they would not connect the call if caller ID was withheld. I was able to prove they were retaining that data without my consent because they rang me back despite me asking for a written response via email.
I contacted the regulator who asked me to write to the data protection officer named on the privacy policy and to ask them to confirm to me in writing under GDPR the lawful basis they were relying upon to obtain my phone number (personal data) without my consent, to use my phone number without consent and to confirm what other purposes they were using my personal data for, which organisations they were sharing it with.
I got a similar reply to yours about terms and sent that to the regulator, they took up my case and have told the company to make changes to their phone system to stop this practice If the company does not comply then they will get a fine. The company are spending over a billion this year alone on new stores and getting tax breaks for doing so, therefore their potential fine could be huge if they do not comply. It has not taken very long either.
It looks as if I will have to do something similar with Roku because I have never consented to any of this sharing of my data. Regarding Netflix I am curious to know if Netflix are aware that Roku is gathering this data because Netflix do not seem to have an option to prevent it Considering the risk to Netflix itself to take steps to protect customer data I could see them preventing Netflix from working on Roku. Companies must take reasonable steps to prevent data being collected without permission. One of our ISP's was fined 500,000 under the old system because they failed to do this on their corporate network and had customer data stolen. If that happened now it would be on the up to 9% scale that was added in 2018 to make companies take GDPR seriously.