Concorde had the issue of extremely high operating costs and low capacity. I don't think maglev has anywhere near the same problem, at least in terms of operating cost.
Nobody has built a maglev system that doesn't have very high operating costs yet. To be fair all of the extant systems are short haul or prototypes but there's still the question of if they will be able to reduce the costs with scale or if they're fundamental to the technology.