[Xylakant]

Your quote is disingenious since it cuts the following, quite crucial sentence. The full paragraph reads:

  Sexism
  
  Using gendered terms like “dude” or “guys” to address a
  mixed-gendered group of people contributes to furthering 
  exclusion of underrepresented individuals. We strongly
  advise avoiding gendered pronouns as well as gendered
  terms.

The whole short paragraph is listed in the "please pay a little attention to this" section of the CoC under the following introduction:

  Inclusive language
  
  In our commitment to a harassment-free and inclusive
  environment we strongly believe it’s important to pay
  attention to harmful language patterns.

It's a fair assessment. It's certainly not obvious to foreign speakers - it certainly wasn't for me - but isn't it fair to ask people to think about the words they're using? To point out common speech patterns that may make other people unwelcome and ask them to avoid them? Why not use "folks" or "people" instead of "dudes" and "guys" to refer to groups of people of all genders? Would you as a presumably male person feel included if someone refers to your group as "girls" or "ladies"? Would you prefer if people used that in their talks?

Now, that this pattern has been pointed out to you, you can still feign ignorance and deliberately still use "guys" and "dudes" to refer to people that do not identify as guys and dudes but that would just make me refer to you as "boneheaded impolite dick" even though you might not identify as such.

[saintPirelli]

No, boneheaded impolite dick is fine dude.