Is it possible to replace pseudo-random in a language globally?

Many languages contains both "secure" and "insecure" PRNG functions. What the possible consequenceses could be there if we make obsolete insecure implementation by making aliases?

"Insecure" PRNG is usually very fast and produces easily predictable sequences based on a seed. "Secure" PRNG is usually uses PRNG from underlying OS/kernel which in most cases is secure.

Note 1: This question is a language-agnostic as it's a very common pattern, but answers could be per-language.

Note 2: We are not speaking about history and old slow computers