Skip Account Fields Filter

What would be the correct way to set pmpro_skip_account_fields to false? The following didn’t seem to work:

`$skip_account_fields = apply_filters(“pmpro_skip_account_fields”, “false”);

When the filter is set to false, is the Username that is automatically generated random? Or is the signup email used?

https://wordpress.org/plugins/paid-memberships-pro/