I think for a realistic comparison we would need to see LLMs benchmarked with and without a "use Memelang for queries" prompt (and a short file somewhere explaining the syntax). I think it's unlikely that the token-efficiency of Memelang would provide much benefit for current LLMs; my intuition is that much more tokens would be spent on reasoning and mistakes in Memelang than are saved from just using SQL (SQL queries aren't usually that long anyway??).

In the few public reasoning traces from recent OpenAI models, we see a lot of "grug speak" as it is token-efficient, and they presumably trained the models for token efficiency in reasoning. It is indeed not too much of a leap to see future token-efficient programming languages.