It wasn't even a fight, Captain America with just his shield and wits would have been written giving Thor more of a fight than Galactus. Bear in mind this Galactus had recently consumed 5 giant planets. This should've been Galactus in Celestial busting mode. I am a big Thor fan, one of the biggest, but this was bad/lazy writing. I have no idea why Thor was able to take the power cosmic away from Galactus.
I wanted Thor to have some good showings after everything the previous writer put the character through but this was an over correction. There has to be a balance between Thor being whipping boy and the other end of the spectrum where he looks ready to take on The Living Tribunal.
On a side note, I don't know about you guys but I'm starting to have Thanos Fatigue.
....about him giving more of a fight against Thor, is extremely bad writing. That's my problem with comic books, they tend to give the underdog a huge boost, even if it makes no sense.
With the Thor and Galactus fight, it's been established before that Thor can absorb energy attacks and re-direct them against his opponents. Once, he even said that he can SURELY absorb a blast that can destroy the Earth....once, he absorbed a blast that can destroy a galaxy and redirect it to a dying star and re-energized it. Once, Thor absorbed the magnetic forces of the planet and redirected it against a Celestial. He can absorb energy to his hammer...that is well established. In the Thor and Galactus fight, Thor simply absorbed the Power Cosmic blasted by Galactus and used it against him. That power and ability is well within Thor's capability. The fact that it has been rarely shown by recent writers is part of the problem. Donny Cates wrote a very plausible scenario how Thor (powered by the Odin Force and Power Cosmic) could beat Galactus. The fact that Galactus absorbed 5 planets just meant that there were far more power for Thor to absorb. If this was against, say, Mangog, the fight would be different because Thor has no energy attack to absorb. Galactus blasting Thor with the power cosmic created the perfect scenario for Thor to win.