One can and will be thrown under the bus by managers and seniors if and when benefits them.
Although all the good things you hear about the big 4 companies are true, the bad are true as well.
Personally I was discriminated against for being LGBT - this was constant; I spoke to HR and filed an ethics complaint only to be told to get over it.
The result was, long term my, career at PwC was limited.
Be careful when you speak up in the southern offices; the main firm policy may be inclusion, but the actual practice varies from office to office.
It's sad, but our southern offices are still not as progressive as the rest of the firm.