Otherwise, you can put non-Unreal games on EGS, and you can put Unreal games on other stores. EGS does not give you benefits if you choose to publish an Unreal game on EGS, and I'd be surprised if all the games EGS buys exclusivity for are Unreal games.
Epic does sell their own games on Epic Game Store, but they also sell most of their games on Steam too (with the huge exception of Fortnite, though it's free to play)
This is false. If you sell a UE game in Epic's store they don't charge the engine licensing fee.
Here's the docs, search for Epic Games Store in this FAQ. They waive the 5% royalties when sold on Epic Game Store. https://www.unrealengine.com/en-US/faq
I'm not sure how "I think..." conveys certainty.
It's just an abrasive thing to do running around going "False!" and "Wrong!" on the Internet. So yeah I'll give you flak for it.
I put in effort to try to not be abrasive because people call that out when I do. You're just receiving the same.
He didn't attack you or act abrasive. You are right that "I think" is not supremely certain language, but it does actually carry certainty with it since you're not saying "I don't know anything about this, but I think..."
Conclusion: I believe you're being a bit overly defensive, and should relax a little. He wasn't personally attacking you, he was saying you were false when you were objectively false, without much in the way of personal insult or even arrogance, and cited his source reasonably well.