Choosing 2FA segregates users into two buckets. Most people are satisfied with the risk of allowing password reset emails and social engineering attacks. They don't pick 2FA.
The rest are generally more sophisticated users, and are willing to risk loss of the entire account if they lose their credentials. That's the price for an overall increase in account security. From this perspective, it makes sense to provide backup codes as another tool in the DIY account-management toolbox.
These buckets oversimplify the situation, but they help explain why backup codes are offered as last-ditch authentication for 2FA.
The rest are generally more sophisticated users, and are willing to risk loss of the entire account if they lose their credentials. That's the price for an overall increase in account security. From this perspective, it makes sense to provide backup codes as another tool in the DIY account-management toolbox.
These buckets oversimplify the situation, but they help explain why backup codes are offered as last-ditch authentication for 2FA.