For what it's worth, I obtained a way to bypass any rate limiting and quota/Fair Use systems, and basically have unlimited Internet speed and no data cap on any

For what it's worth, I obtained a way to bypass any rate limiting and quota/Fair Use systems, and basically have unlimited Internet speed and no data cap on any SIM card of one carrier. I reported the finding to them, after many escalations they in the end gave me an expensive phone as a gift and fixed the issue. It was in Serbia, so I'm not sure how relevant that is to the EU.