Running :checkhealth reports the version as a table: 0x7f01f79278d8 instead of an actual version string:
kickstart: require("kickstart.health").check()
kickstart.nvim ~
...
- OK Neovim version is: 'table: 0x7f01f79278d8'
 
If I call:
:lua vim.print(vim.version())
 
it will print the following:
{
  api_compatible = 0,
  api_level = 11,
  api_prerelease = false,
  major = 0,
  minor = 9,
  patch = 5,
  prerelease = false
}
 
Seems there is an issue with tostring(), this prints table:
:lua print(tostring(vim.version())
table: 0x7f01f79278d8
 
After some more testing it seems that the tostring(vim.version()) works starting with nvim 0.10.0, but since kickstart considers 0.9.4 version as recent enough and the message for old version also uses tostring() I'd say this needs to be fixed.