I think you and your doctor both need to pay attention to what is really going on after a radical prostatectomy. Having you do more at .2 PSA Is the standard of care Not an over treatment. You probably saw the below info, but I want to make sure you do see it because it outlines what can go wrong if you ignore the .2 need for immediate action.

As you can see below if you wait until 2 You will need ADT, With a Gleeson nine and a reoccurrence, you need ADT at almost any level of PSA above .2.

You need to get yourself a second specialist. This wait until your PSA hits 2 after having a radical prostatectomy is not just poor care, it ignores all the guidelines. That is the guideline for what to do if you start off with just radiation.

From Ascopubs about what PSA to do salvage radiation.

≤0.2 ng/mL:
Starting at this level maximizes disease control and long-term survival. Patients treated at PSA < 0.2 ng/mL achieve higher rates of undetectable post-SRT PSA (56-70%) and improved 5-year progression-free survival (62.7-75%).
Delaying SRT beyond PSA ≥0.25 ng/mL increases mortality risk by ~50%.

0.2–0.5 ng/mL:
Still effective, particularly for patients with low-risk features (e.g., Gleason ≤7, slow PSA doubling time). The Journal of Clinical Oncology recommends SRT before PSA exceeds 0.25 ng/mL to preserve curative potential.

0.5–1.0 ng/mL:
Salvage radiation remains beneficial but may require combining with androgen deprivation therapy (ADT) for higher-risk cases.