This is not an issue.
Your page includes a header and footer. When you restore the index or any page, you restore the content between the header and footer. And from your example we can see it worked.
You don't find a lot of sections because they are located in the footer (see my screenshot below)
To restore those sections you need to restore your footer. To see all modified files you can go to Project Configuration > Restore
Or to target only the footer go to Code Editor > config > footer.html => right click => restore
Then reload your Pagebuilder and magic should happen