phrases - A formal synonym/expression for "saying that"

Here are a few options for your consideration:

state verb: 3rd person present: states; past tense: stated; past participle: stated; gerund or present participle: stating

1. express something definitely or clearly in speech or writing.

synonyms: express, voice, utter, put into words, declare, affirm, assert; see, Google state

In your example: To state [or, Stating] that rape culture is an environment where emotional and physical violence against women is the norm is, in a way, normalizing and excusing sexist behaviors and beliefs.

assert verb: gerund or present participle: asserting

state a fact or belief confidently and forcefully.

synonyms: declare, maintain, contend, argue, state; see, Google assert

In your example: To assert [or, Asserting ] that rape culture is an environment where emotional and physical violence against women is the norm is, in a way, normalizing and excusing sexist behaviors and beliefs.

characterize verb: gerund or present participle: characterizing

1. describe the distinctive nature or features of.

synonyms: distinguish, make distinctive, mark, typify; see, Google characterize

In your example: To characterize [or, Characterizing ] rape culture as an environment where emotional and physical violence against women is the norm is, in a way, normalizing and excusing sexist behaviors and beliefs."