I recommend reading https://keymaterial.net/2025/11/27/ml-kem-mythbusting/, which explains (1) why it's not possible for ML-KEM (the thing most people are using for post-quantum encryption) to be backdoored the way Dual_EC_DRBG was, and (2) some of the reasons some people don't like hybrids, not all of which are good but none of which should serve to undermine confidence in ML-KEM's security.