Natural languages can’t be descriptive or prescriptive, they merely are. Grammars for those languages can be either descriptive (i.e., describing the language as used by speakers) or prescriptive (i.e., prescribe how the language should be used).
In the former case, it’s perfectly fine to freely split infinitives; in the latter it is something up with which one does not put.
https://en.wikipedia.org/wiki/The_New_York_Times_Manual_of_S...
The one that always looks odd to me is C.I.A. and F.B.I.
NYT sets typographic conventions. For decades. They publish an entire in-depth guide on their style, and they adhere to it with great consistency.
They've thought a whole lot more about the issue than you, or I, ever have or ever will.
PS: Beware The New Yorker and The Atlantic.