I find it hard to avoid the fact we are literally being called a Superhero. Like, thats just stated in the text.
Like, the Gems didn't attack us, hell we didn't even attack them until the united states began to push em back. So it wasn't us getting revenge for them provoking us. We then began liberating cities under siege, and helping push forward. We didn't make a deal with the Feds or anything, we simply chose to save the day (Mostly to spend time with Stickybeard).
We had basically no benefit for doing this in universe as a villain. Out universe its because the Gems are near "Our Territory" and the most obvious existential threat, but like; They weren't actually that close to Virginia which is where I believe KND take. Furthermore no other villains were attacking them either; they were dangerous but a distant danger to a lot of people. Even Mandark in his constant attempts of One Upsmanship simply sent military aid instead of assaulting himself.
We can argue it makes sense to us as Father all we want; thats not the issue here. It's how the outside world sees us. They see a man saving an entire nation for seemingly no reason. This man has also made a giant defense robot and makes a ton of office supplies. We haven't been doing enough Supervillainy to counter act this action.
Honestly simply covering the election should be a good starting point. The other major News Networks deem it "Not Exciting" enough to cover.