Devstral 2 is free from the API. That has to be a bigger point to what makes it better. The price to performance ratio is practically better in every way.
Does it matter if the performance is slightly worse when it is practically free?
Yes, but if it's actually competitive that won't last that long. Mistral will do the same as google (cut their free tier by 50x or so) if they ever catch up. Financially anything else would make no sense.
Of course currently Mistral has an insane free tier, 1 billion tokens for each(?) of their models per month.
Are they? IIRC their best model is still worse than the gpt-oss-120B?