Tendinopathies are pretty unpredictable and can cause trouble for a long time. It’s chronic in the sense that by now the tissue in his tendon will have changed, and will never be the same as before.
My guess is they decided to take some months of so they could try and build new capacity in the tendon by making it stronger and thicker. Some refer to this as the “donut theory” meaning the middle/core of the tendon will have changed permanently, but you can add new healthy tissue around it with controlled training.
There is a lot of research being done about the optimal way to load tendons in order to stimulate growth which still isn’t a 100% clear. Essentially, fast loads (running, jumping etc) puts the tendon under a lot of stress but not adequate amounts of strain to stimulate positive adaptations. So maybe they decided to take him out in order to completely control his training/load on the tendon for a few months.
So yeah basically it’s sorta chronic But can be improved a lot. Maybe he comes back and can play 90 minutes week in week out for the second half of the season if we’re lucky. He’s not doomed to play 60min only for the rest of his career.