Vim ignores `filetype indent off`

Question

I don't have a personal vimrc. I use /etc/vimrc. The last 2 lines are:

let testvar=999
filetype indent off

I confirmed execution at the vim prompt using :echo testver, which displays 999.

I tried to create a Matlab file using gvim RndSquare.m. My first typed line is:

function m = RndSqure( n )

The following line always start indented, which I don't want.

The only way to prevent it seems to be to create ~/.vim/indent/matlab.vim containing let b:did_indent = 1. I also had to create tex.vim containing the same line, for the same reason.

I don't want to create a gazillion files, one for each file extension, and all containing the same line. Why are the last 2 lines in my vimrc ignored?

Vim version:

VIM - Vi IMproved 8.1 (2018 May 18, compiled Jul 28 2019 14:56:47)
Included patches: 1-1772
Modified by <cygwin@cygwin.com>
Compiled by <cygwin@cygwin.com>
Huge version with GTK3 GUI.  Features included (+) or not (-):
+acl               -farsi             -mouse_sysmouse    -tag_any_white
+arabic            +file_in_path      +mouse_urxvt       -tcl
+autocmd           +find_in_path      +mouse_xterm       +termguicolors
+autochdir         +float             +multi_byte        +terminal
-autoservername    +folding           +multi_lang        +terminfo
+balloon_eval      -footer            -mzscheme          +termresponse
+balloon_eval_term +fork()            +netbeans_intg     +textobjects
+browse            +gettext           +num64             +textprop
++builtin_terms    -hangul_input      +packages          +timers
+byte_offset       +iconv             +path_extra        +title
+channel           +insert_expand     +perl/dyn          +toolbar
+cindent           +job               +persistent_undo   +user_commands
+clientserver      +jumplist          +postscript        +vartabs
+clipboard         +keymap            +printer           +vertsplit
+cmdline_compl     +lambda            +profile           +virtualedit
+cmdline_hist      +langmap           +python/dyn        +visual
+cmdline_info      +libcall           +python3/dyn       +visualextra
+comments          +linebreak         +quickfix          +viminfo
+conceal           +lispindent        +reltime           +vreplace
+cryptv            +listcmds          +rightleft         +wildignore
+cscope            +localmap          +ruby/dyn          +wildmenu
+cursorbind        +lua/dyn           +scrollbind        +windows
+cursorshape       +menu              +signs             +writebackup
+dialog_con_gui    +mksession         +smartindent       +X11
+diff              +modify_fname      +sound             -xfontset
+digraphs          +mouse             +spell             +xim
+dnd               +mouseshape        +startuptime       +xpm
-ebcdic            +mouse_dec         +statusline        +xsmp_interact
+emacs_tags        -mouse_gpm         -sun_workshop      +xterm_clipboard
+eval              -mouse_jsbterm     +syntax            -xterm_save
+ex_extra          +mouse_netterm     +tag_binary
+extra_search      +mouse_sgr         -tag_old_static

Answer 1

I don't have a personal vimrc.

Then Vim sources $VIMRUNTIME/defaults.vim You can see this by issuing :scriptnames

Why are the last 2 lines in my vimrc ignored?

They are not. The last line gets effectively cancelled by the line filetype plugin indent on from defaults.vim, because it gets sourced after it.

The last 2 lines are:

This is a huge mistake, because you are trying to abandon indenting, while you rely on defaults to switch filetype on. That cannot work. So you must create ~/.vimrc If you need at least filetype stuff without indents you have to add filetype plugin on to it. Otherwise you can keep it empty.