Is this evidence about the power of humans post King Kai?

[withheldforprivacy]

When Kai tells them that Freeza easily killed Vegeta, they're shocked. Also,
humans do not know what exactly happened on Namek, so they don't know
about Vegeta's power increases. That means that they still consider
impressive someone who can easily kill a 18.000 power level.

 

[Void]

Well, they all actually died before they could even see Vegeta in action. They only know he is strong like Nappa, Piccolo only determined Vegeta was stronger after Yamcha, Ten, and Chaozu had died.

Didn't King Kai mention something about Vegeta continuing to get stronger?

 

[Evil Vegeta]

I don't think that really tell us much. They've supposedly been keeping up with everything, so naturally they'd expect Vegeta to be a powerhouse on Namek. Wouldn't make much sense for them to expect Vegeta to be utilizing the same power from Earth when everyone else has been improving. Jack pretty much explained why they wouldn't know his capabilities, anyway.

Then again, Tien was able to deduce that Goku could use Kaio-Ken x10, so there's no telling what they might know.

 

[Let's Go Fearless!]

Didn't King Kai told them about the Zenkai?

 

[Pyro]

There's next to nothing regarding the humans on Kaio's planet other than them being inferior to Piccolo when he left, and he should be in the low hundred thousands at best.

 

[Captain Cadaver]

Kaio probably kept them up to date with everything going on. They'd at the very least know that Vegeta was far above Piccolo, who's strength they should've been aware of, so I'd say this means little.

 

[theallpowerfulpuipui]

When Kai tells them that Freeza easily killed Vegeta, they're shocked. Also,
humans do not know what exactly happened on Namek, so they don't know
about Vegeta's power increases. That means that they still consider
impressive someone who can easily kill a 18.000 power level.