Though, ironically, at least for some tasks, Russian is a better choice than English.

Back in 2025, a research paper titled "One ruler to measure them all: Benchmarking multilingual long-context language models" (https://arxiv.org/abs/2503.01996) published some benchmark results for finding and aggregating information found in long documents, measured by language. English ranked 6th in accuracy.

The top performers out of the 26 they measured were, in order: 1. Polish, 2. Russian, 3. French, 4. Italian, 5. Spanish, 6. English, 7. Ukrainian, 8. Swedish, 9, Portuguese, 10. German.