TABs not displaying properly in Neovim-from-scratch files

[w-r-z-k]

With either the tokyonight or onedarker colorschemes it appears that characters after TAB are missing but they are actually there (see the words 'return' or 'local'):

[w-r-z-k]

It also isn't converting tabs to spaces even though expandtab is set to true in lua/user/options.lua

Oddly typing :set expandtab shows nothing even though :set tabstop and most other variables return their values.

[w-r-z-k]

I see that many of the files in the repository have TABs instead of spaces. That's in spite of the options.lua file saying expandtab = true. And they all display badly as above using the configuration files themselves.