It says individuals have a right to have data erased in a number of circumstances, these are
Where the personal data is no longer necessary in relation to the purpose for which it was originally collected/processed.
When the individual withdraws consent.
When the individual objects to the processing and there is no overriding legitimate interest for continuing the processing.
The personal data was unlawfully processed (ie otherwise in breach of the GDPR).
The personal data has to be erased in order to comply with a legal obligation.
The personal data is processed in relation to the offer of information society services to a child.
I would guess online gambling sites can easily claim they have to keep the data for the reason it was originally collected.
It might be interesting to try and claim the data was unlawfully processed if its possible to claim iesnare is effectively sharing information on you without consent via sharing data about your device between bookmakers. Isn't there an ongoing investigation into that at the minute?