Have you had an endoscopy at all during all of this? I was on a PPI and after my 3rd endoscopy, my GI said to never take it again as my digestive tract cells were hypertrophic. If you have had GERD for a long time, have you been tested for SIBO (small intestinal bacteria), a fungal infection, a yeast infection or parasites? All of these can be culprits and need to be treated. A PPI only treats to the symptoms, not the cause of your symptoms. The cause(s) need to be eliminated. Your gut biome can be very unhealthy and needs building back up to deal with any of these infections, in addition using prebiotics and probiotics. This has been my journey and it takes time and the right doctor to test you and knows how to test and treat. Your vitamin and mineral levels also need testing to see what you are deficient in - a poor gut biome is not allowing your digestive tract to take in what is needed for health if your gut cannot digest food you are eating.
Best to you in finding answers.