I've been following this pull request thread involving the removal of gendered pronouns in an open source project with interest. It's an obvious change to make a project more inclusive, yet it was met with:

Sorry, not interested in trivial changes like that.

A patch was finally included, but then reverted by the same commenter.

This is dumb. In English, choosing gender-neutral pronouns is simple. Here's how, using the aforementioned reverted patch as an example:

• Gendered: The user needs to know that some data has already been sent, to stop him from sending it twice.
• Neutral: The user needs to know that some data has already been sent, to stop them from sending it twice.

In the past, I've heard people gripe about the use of "them" to reference a singular person, but it is actually correct English. It's called the "epicene they". Shakespeare used it; Jane Austen used it; you can use it.

One more time:

• Excludes 50% of your users: The user must feel comfortable using your software, otherwise he may choose another product.
• Inclusive: The user must feel comfortable using your software, otherwise they may choose another product,

There's no extra effort involved. Have at it.