Is treatment working?

I'm going to echo what @jeffmarc and the others say. It seems based on the clinical data you describe, you are castrate resistant. If I understand the guidelines from NCCN and AUA correctly, you generally continue with thye ADT and ARI but now other treatments are in play.

Chemotherapy is certainly one of them
MDT using whatever form of radiation is another
Has the medical team discussed:

Targeted therapy (PARP inhibitors)
For patients with specific genetic mutations, targeted therapy can be highly effective.
Olaparib (Lynparza) and Rucaparib (Rubraca): Used for patients whose tumors have mutations in DNA repair genes, such as BRCA1 or BRCA2.

Radiopharmaceutical therapy - this approach uses radioactive substances that are selectively delivered to cancer cells.
Lutetium-177 (¹⁷⁷Lu)-PSMA-617 (Pluvicto): A targeted therapy for patients with PSMA positive mCRPC.
Radium-223 (Xofigo): A radioactive drug that is targeted to bone metastases to relieve pain and improve survival.

Immunotherapy
Sipuleucel-T (Provenge): A cellular immunotherapy that is customized for each patient and stimulates the immune system to attack prostate cancer cells.
Pembrolizumab (Keytruda): Approved for patients with tumors that have specific genetic features, such as high microsatellite instability (MSI-H) or high tumor mutational burden (TMB-H).

Palliative and supportive care - This type of care focuses on managing symptoms and improving comfort, which is a key part of treating mCRPC.

Factors influencing a decision:
Previous Treatments: The sequence of therapies is important, with some medications recommended for use after other treatments have failed.
Biomarker Testing: Genetic testing for mutations (e.g., in DNA repair genes) can help identify patients who may benefit from targeted therapies like PARP inhibitors.
Disease Location: The presence of bone metastases versus visceral metastases can influence the choice of therapy, such as the use of Radium-223 for bone-focused disease

This is "old" but may be useful - https://www.urotoday.com/video-lectures/nccn-2024/video/4172-2024-nccn-guidelines-update-metastatic-castration-resistant-prostate-cancer-treatment-rashid-sayyid-zachary-klaassen.html#:~:text=Rashid%20Sayyid%20and%20Zachary%20Klaassen,profiles%20and%20prior%20therapies%20received.

Kevin

You have provided a lot if information most of which I will have to do some reading to understand what they all mean
Thanks

From my perspective, your medical tram should be leading the discussions with you about these.

Sadly, many do not.

So, it may fall upon us to drive the conversation...that necessitates us doing our homework, informing ourselves so that we can drive the conversation.