It is pretty common to assume that email addresses aren't case sensitive since many email providers treat them that way. Email addresses absolutely are case sensitive so you need to preserve case when storing them and be careful about case when using them.
This makes email addresses particularly unsuited to being used as a natural key. Most people treat them as case insensitive and you need to work around that, but you can't safely just treat them as case insensitive yourself.
It is pretty common to assume that email addresses aren't case sensitive since many email providers treat them that way. Email addresses absolutely are case sensitive so you need to preserve case when storing them and be careful about case when using them.
This makes email addresses particularly unsuited to being used as a natural key. Most people treat them as case insensitive and you need to work around that, but you can't safely just treat them as case insensitive yourself.