Colorscheme not found if used from a VeryLazy autocmd

[Shaobin-Jiang]

A minimum config that works correctly:

local lazypath = vim.fn.stdpath("data") .. "/lazy/lazy.nvim"

if not vim.uv.fs_stat(lazypath) then
    vim.fn.system({
        "git",
        "clone",
        "--filter=blob:none",
        "https://github.com/folke/lazy.nvim.git",
        "--branch=stable",
        lazypath
    })
end
vim.opt.rtp:prepend(lazypath)

require("lazy").setup({
    spec = {
        { "folke/tokyonight.nvim", lazy = true }
    }
})

vim.cmd "colorscheme tokyonight"

Basically it sets up tokyonight as the colorscheme. Despite my having lazy loaded the plugin, lazy.nvim has created a ColorSchemePre autocmd that ensures any colorscheme plugin not loaded when the colorscheme command is executed be loaded first. So I assume that, since this would work during startup, it surely would work as well if I postpone the colorscheme command till VeryLazy, and this is how I modified the code:

local lazypath = vim.fn.stdpath("data") .. "/lazy/lazy.nvim"

if not vim.uv.fs_stat(lazypath) then
    vim.fn.system({
        "git",
        "clone",
        "--filter=blob:none",
        "https://github.com/folke/lazy.nvim.git",
        "--branch=stable",
        lazypath
    })
end
vim.opt.rtp:prepend(lazypath)

require("lazy").setup({
    spec = {
        { "folke/tokyonight.nvim", lazy = true }
    }
})

vim.api.nvim_create_autocmd("User", {
    pattern = "VeryLazy",
    once = true,
    callback = function ()
        vim.cmd "colorscheme tokyonight"
    end
})

And now, neovim complains about not being able to find the colorscheme.

This baffles me since VeryLazy occurs well after startup. In this second piece of code, when I use colorscheme, the ColorSchemePre autocmd ought to have been set up correctly, and yet it does not.

I know how to solve this. Just using require("lazy.core.loader").colorscheme("tokyonight") does the trick. However, I am at a loss as to why the matter should exist in the first place.