Depending on the jurisdiction, the minimum required storage time for medical data varies - but it needs to be kept around usually. Patients can, within that time frame, request that data to be provided, but may be required to pay some fee to cover the material costs. In my jurisdiction, this time frame is 10 years, and radiology data is usually provided as a paper slip with a link and password, valid for 1-2 years, or DVDs on request.
Keeping that data around and managing requests for it is a part of why older physicians are so keen to sell their practices to younger doctors here - they can pass on the duty of keeping up with storing the data that way.
FWIW, I'm in a jurisdiction with a 10 year retention requirement, and also have had no issues getting imaging data from beyond that (on DVD, of course - one department even had a side hustle selling external DVD drives for $50 on the side; they even offered to drop the files onto a USB drive for free).
Keeping that data around and managing requests for it is a part of why older physicians are so keen to sell their practices to younger doctors here - they can pass on the duty of keeping up with storing the data that way.