He can damage him sure, but Speedfreak has a shiet ton of obstacles to get through. Keep in mind the standard starting distance which is .5km. That's a little over 5 football fields. First line of defense is lightning. This is literally a one-shot if Odinson opens with it. Let's say he doesn't. Now Speedfreak has to deal with Thor's other tools. Remember unlike Hulk, Thor can fend off Speedfreak's attack with Jarnbjorn and his black uru arm. Hulk didn't have that luxury, but here Odinson has it in spades. The idea that he can easily be cut up especially at his vitals is very hard to accept. Plus he's vastly more superior in skill than Speedfreak.For starters he's shown great reflexes and using his legs.
Mjolnirless young Thor continuously dodges "blast after blast".
http://i.imgur.com/ArF1jvB.jpg
Continuously dodges 3 meteorites with "unabated speed" that was powered by the Odinforce.
http://i.imgur.com/c5Q7eRu.jpg
He's also shown great reflexes and reaction with his arms.
Shatters his surroundings then hurls multiple fragments at his opponent by batting them away.
http://i.imgur.com/gRZUDH6.jpg
Bats away a barrage of bullets.
http://i.imgur.com/KeKA9Fc.jpg
Makes two full swings at flying debris before a speeding Gladiator reaches him.
http://i.imgur.com/7VNkVXd.jpg
Catches a tank shell with his bare hands.
http://i.imgur.com/UV4AhLf.jpg
Parries a sniper's bullet in mid-flight.
http://i.imgur.com/2NA17zx.jpg
http://i.imgur.com/9ij4o0f.jpg
He can also cover distances with great speed.
From a distance, Thor is able to save a child who is falling off a cliff. Notice Thor is already in position to catch the child who literally just went over said cliff. Might as well call it teleportation.
😂
http://i.imgur.com/c3V3k06.jpg
http://i.imgur.com/1bRwWNV.jpg
Reaches Surfer from a distance before he can fire off another blast. You see that blur with a bit of lightning at the bottom left panel? Yeah that's Thor running towards Norrin.
http://i.imgur.com/3UZyj6x.jpg
And for good measure.
He is able to perceive Skuttlebut who just blew by him. We know Skuttlebut was travelling faster than light just three pages prior.
http://i.imgur.com/ao1PZUZ.png
We know he sometimes he underperforms when going up against vastly weaker opponents that are supposedly fast, but it's not much different from someone tagging Flash, Gladz, Surfer, or any other character with tremendous speed. Now I'm not saying he is on those levels(being a speedster is not his thing after all), but the idea that Thor is a snail is just stupid and contradicts many of his on panel showings.