Make Spreadsheet Editable By Everyone

I want to be able to make the spreadsheet by anyone who can view it, not just the admin logged into WP.

I am just going to have the page password protected instead of making people create an account.

Let me know if this is possible! Thanks so much.

you could customize logic of readonly mode:
wp-content/plugins/spreadsheet/spreadsheet_data.php includes the follow code:

if (!isset($available_to[$usertype]) || $available_to[$usertype] == false)

So you may provide required logic here.

That worked for me. Thanks!