When someone tells you "good job guys", is that offensive to you?

Seriously? What if one of the "girls" took exception to that? She doesn't consider herself a "girl", she is a "woman". The term "guys" isn't just male when it encompasses a group of people. This politically correct stuff is really getting out of hand

Go to your EO office and get a copy of the "offensive word" list. You will be shocked at some of the stuff off it.

The terms "guys" and "guys and girls (gals)" has absolutely no difference. The word guy is in of itself gender neutral. While it is commonly used to refer to males, it ALSO accurately refers to females. It is just as accurate to point to a group of gentlemen and say "Those guys" as it is to point to a group of ladies and say "Those guys". It really is just semantics. And maybe feminism, but let's not get our panties in a twist here.

I've always taken that as a figure of speech and not paid much attention to it, especially in the circumstances you described. It also depends on who's saying it. "Good job guys" coming from a senior means something different than a subordinate. To me, "Good job guys" from a subordinate is an unwelcome term of familiarity and gets my immediate attention.

Colloquially speaking, "guys" is an acceptable term to refer to both males and females. That's not how it started but that is how it has been used for at least a couple of decades. I suppose if someone is truly offended by this they can tell you about it. I don't see how this affects equal opportunity so I think you're fine and the SFC who corrected you was simply taught to be overly sensitive to not offend the maximum number of people. We do often go too far in this regard as is the military's way.

CH (CPT) Heather Davis, Ma'am, the terms "Guys" "you guys"and "Y'all" are pretty much interchangeable and accepted almost universally as a form of generic group address, except by only the most ridiculously socially oversensitive among us.
The good news for your SFC is that if that's the biggest thing he has to worry about, his stress level should be pretty low.

This is what I consider "E-splittiing-hairs-O". Yes, certain words do carry certain unintended meanings behind them but when CH (CPT) Heather Davis said "Good job GUYS", I see it as the collective use of the word. She wasn't trying to exclude anyone from the kudos. It is much of the same as when you use the collective "you" when talking to a group of people. If I'm standing in front of a group of people and say "You did a great job" am I excluding someone because of the word I used? No. It is ridiculous to think that someone would have to be pointed out in order to feel included. When you work as a team, you celebrate or fail like a team. You are included in all the "guys", "you", "them", or whatever wording used.

It's a generic term, not specifically gender driven. If it will make the PC Police happy, consider using the word "folks" instead. You could point out that by specifying "guys and girls" they are defeating the purpose of the teamwork concept by dividing the group with gender labels.

This is completely ridiculous, but then again, it should be expected in this new PC military. I say this all the time, and none of my Sailors have ever complained to me about it, and they are pretty open with me.

No I did it a lot of times. I think the sincerity of the message is what counts.