I agree with this. I have practiced meditation for several years, including near month long retreats, originally in an attempt to feel less derealization, and what it brought me did not feel like an antidote to derealization. I felt more present, I had a clearer vision of what was happening in my mind or around me, but I was still detached from things. I don't think it helped my DR at all. To me these are two separate things. But I have read that some people could reduce stress thank to meditation and did experience less DP/DR.