@nocturnalman is right when he says it's up to scientists to develop treatments. If you're not a scientist maybe you can focus on raising awareness. Having a mental health treatment community that knows what depersonalization is can make a difference even if a perfect cure doesn't exist. Research is also possible in the absence of a perfect cure. Many treatments for depression and psychosis exist but few people characterize them as absolutely effective.
There's no need to despair. We can be good, happy, functional people despite depersonalization. I'm not a proponent of fruitlessly trying to solve problems which aren't all that serious. Should a beautiful or normal looking person get extensive plastic surgery? Dissociation can be dangerous if it interferes with important responsibilities or causes lack of awareness when operating heavy machinery. Societal awareness and acceptance of depersonalization syndrome are key in my opinion. However, we shouldn't fall into the trap of all or nothing thinking, veering to the other extreme where we ignore depersonalization syndrome entirely. Depersonalization can signal physical or mental problems we're experiencing. It's often an indicator of another physical or mental disorder.
In terms of psychiatric treatment, the best course of action we currently know is to treat comorbid disorders. People with chronic depersonalization often have comorbid disorders. These can be treated directly with psychopharmacological interventions, talk therapies, and social interventions. Self-directed therapy and lifestyle changes can also help. Depersonalization disorder is often conceptualized as a dissociative disorder. Talk therapy is the most commonly recommended direct form of treatment for dissociative disorders.
Many people with chronic depersonalization spend years looking for solutions outside themselves. It's hard for them to accept their brains aren't functioning in a more preferable way, but imperfection is a part of life. Take Alzheimers for example. Life is unfair but we try to make the most of it.