While I don't disagree that inflation would affect the purchasing power of a UBI, I think you discount the fact that a fairly significant percentage of the US i

While I don't disagree that inflation would affect the purchasing power of a UBI, I think you discount the fact that a fairly significant percentage of the US is already on some form of safety net or welfare program. Whether it be "food stamps" (vouchers for food, reimbursed as governments like a UBI), SSDI disability (fixed payments due to work disability or structural changes in an industry), unemployment insurance payments (temporary fixed payments), Social Security (long-term fixed payments), Section 8 housing (vouchers for housing), etc, there are plenty of examples where the issues you raise are already affecting the recipients. I've heard anecdotally that many doctors have ceased accepting MedicAid (suggesting that medical inflation has already outpaced the government's ability to reimburse). I think your argument should focus more on why the UBI is not any better than the morass of existing programs, some of which have disincentives for people getting off of the program. I'm not yet convinced is is either better or worse, but I don't think inflation is a deal-killer for UBI because it's already an existing issue in currently running programs.