The Galar fossils are one of the greatest things in all of Pokemon, and among them Dracovish reigns uncontested. Speaking of Mr. Fish...
This question is good enough to carry an entire WolfeyVGC video. I mean that as a compliment. Please appreciate I put the same amount of effort into my answer as a famous Youtubist would.
Super-effective:
"Humans are the real threat" is true in zombie movies and in pokemon battles.
Grass means trees and flowers, which humans either burn to the ground or cultivate. Either way, green nature has been mastered.
Neutral:
Normal is normal. Humans like normal. Face it, most Human pokemon would be dual-type with Normal.
Fighting humans do pretty well in. Heck, the majority of Fighting-type pokemon are based on human martial arts.
Poison we're no more or less vulnerable to than most living beings; and we put some poison into the atmosphere and water ourselves, which the rest of the planet has much worse troubles with.
Fire, Water, Ground fall in a similar camp; we're not immune to them, but they don't do extra damage either. They plain hurt.
We survived an Ice age, and outlasted our equivalent of Mamoswine - an actual ice-type! - too boot, so it's not that.
Dragons eat our virgins, and dragons get slain by our knights. Call it a draw.
Steel and Rock you could make an argument for as being effective against Humans, after all for large parts of our history we made weapons meant for warfare against fellow humans out of exactly those materials. The fact is a function of their availability and compatibility with our tools, rather than any inherent advantage in killing power, still the justification is there if you need further options for gameplay reasons.
Related, Electric as weakness, in tribute to the Electric Chair, would be a bit macabre.
Bugs do fine with civilization around; ergo they can't be weak to us. By the same token, they have no dominion over us.
Flying is complicated. We're not meant to fly, yet we made it work. Yet in pursuing the dream of flight, people have died and continue to die. Flying represents our hubris. Like Icarus, we've been, at once, super-effective at it and weak to it. Does that balance out to neutral?
Weaknesses:
We are forever doomed to fall victim to Psychics; with how easily fake ones prey on human minds, imagine what a real one would do.
We see shadows where there are none, and do dumb things because of it. The Dark scares us, just as Ghosts hold power over our lives whether they exist or not.
And I agree with others, that a Fairy is a reason to worry. Fairies exist to fuck with us, and are historically good at it.
