The ability to access communications from numbers that have been blocked directly on an iPhone is not a standard feature within the iOS operating system. When a number is blocked, subsequent text messages are prevented from reaching the recipients inbox. A user will typically not receive any notification that a blocked number has attempted to contact them.
The intentional design of this feature is to provide users with control over unwanted communications and prevent harassment. The focus is on preventing messages from being received, thus maintaining privacy and avoiding potential distress. Historically, mobile operating systems have evolved to offer more robust blocking features in response to growing concerns regarding spam and unsolicited contacts.