What do you think of the theory that Tao weakened since his prime? Toriyama said in an interview that Tao was one step ahead of his brother when they were competing, but 22nd Tsuru seems to be significantly above Tao and stomping weaklings like Blue and Bora couldn't have been a particularly power raising activity for Taopaipai
Not sure because even though he is technically hundreds of years old, he didn't seem to be effected so drastically by his old age as Roshi and the Crane Hermit we're.
Eh, I never really understood why anyone would think Tao is so strong. Maybe he's stronger than Chappa, but that's it. All we really hear about Tao in the 22nd is Tenshinhan being pissed that Goku defeated him. Goku says his fight with Kuririn was the funniest he'd ever had and Tsuru even says Goku might have beaten Tao based on how he beats Pamputto of all people, lol.
Roshi was surprised Goku could kill Tao despite having witnessed Kuririn and Yamcha's growth. If everyone and their mama was stronger than Tao from 3 years ago than Goku killing him shouldn't be a big deal.
Chapter: 120, P11.1-2
Context: Goku revealed that he defeated Taopaipai. Tenshinhan did not believe it.
Jackie Chun: “Did you really…take down Taopaipai…?”
Goku: “Huh? You too, gramps? I did so! It wasn’t easy, though…him being so strong and all.”
Jackie Chun: “Taopaipai…said to be the world’s Number One assassin…and this lad…he…he
As for how Goku beat Panputto. It seems more about the specific way he beat him that impressed Tien and the Crane Hermit than anything.
It is not unreasonable to give Goku small gains during the 3-year gap. All he did was roam here and there.
But then, you would have to retcon the events of the Baba arc where everyone witnessed Goku's Karin tower gains so that someone like Chappa isn't so strong.