Tommy Atkins has survived as the standard commercial mango because of a number of factors. Its productive, disease resistant, survives the rigors of shipping and handling well, has a (relatively) long shelf life, and eye-catching color (unfortunately a very important factor).
The problem is that they take an already below-average mango and make it worse by picking it way too early and then "boiling" it before import. This would be an issue for any mango, and applies to some of the better cultivars that are grown commercially as well (Kent and Keitt). So for that reason among others I'll always contend that you are much better off purchasing mangoes grown domestically.
The success of Ataulfo ('Champagne mango') should offer some hope to people who want to see cultivars other than Tommy Atkins. In Europe, varieties other than Tommy Atkins are in a lot of their markets...Van Dyke, Osteen, Palmer, others.