That extreme case may still be worth it, if the result (program + DSL implementation) is easier to maintain than the mainstream alternative (program in a general purpose language).
Besides, it wouldn't be that many DSLs. There are relatively few domains where performance is really critical. Cryptography, rendering, encoding/decoding… that's a few dozens at most, with global impact for each. If those DSL have any positive impact at all, they will be worth the cost a million times over.
Besides, it wouldn't be that many DSLs. There are relatively few domains where performance is really critical. Cryptography, rendering, encoding/decoding… that's a few dozens at most, with global impact for each. If those DSL have any positive impact at all, they will be worth the cost a million times over.