> something that is at parity with Opus 4.5

You're assuming the conclusion

The previous GLM-4.7 was also supposed to be better than Sonnet and even match or beat Opus 4.5 in some benchmarks ( https://www.cerebras.ai/blog/glm-4-7 ) but in real world use it didn't perform at that level.

You can't read the benchmarks alone any more.