It's annoyingly true. I spend half my time editing out prevaricating language like "I think" from emails because I fucking know I've been trained into hedging my opinions, or at least presenting them as though I'm hedging. The worst thing about it is that I generally think that kind of language is a good thing. I'm giving an opinion - usually a well-researched and fairly solid one - but there should be room for someone to disagree with it. Hence the "I think", or "in my opinion". But when you're dealing with men, you'll get steamrollered if you do that, so you have to adjust your language to meet the overly-confident norms of their way of speaking.

I also deliberately drop my voice deeper when giving presentations. It's fucking wild that these things are gendered and that to be seen as authoritative you have to ape masculinity.

I'm also regularly told I write in a masculine way, incidentally.

All that said, if you're aware of the stupid little rules of the game, you can play them up or down to your advantage. Need to find things out and would like someone to maybe let slip more info than they professionally should? Play girly. Wear pretty dress, look as young as you can pull off, pitch your voice on the higher end of normal and use that feminine equivocating language. Then when it comes to implementing changes based on what you've found out, pitch it in the firmest language and the deepest voice in your normal range.

Fucking gender roles, man. Who the fuck came up with those?