Earlier quoted context omitted.
You might just as well say it is the IANA's fault for issuing the IP addresses the malware authors used, or Ford's fault for building the getaway car used in a bank robbery.
Your argument is ridiculous. Turning over IANA or Ford over to Microsoft would not prevent malware or robberies. Turning over NoIP to Microsoft will prevent malware (at least in the short term).
And what about any innocent users of Dynamic DNS who are currently suffering from the consequences of this action? No-IP's statement implies that this is somewhat widespread and due to Microsoft's inability to handle the responsibility it has somehow acquired in this case. Others on HN seem to be posting independent verification of this using standard tools from their own systems.
In short, it is neither obvious that turning over NoIP's domains to Microsoft will prevent malware, nor clear what should happen if it doesn't, and it is certainly not clear that Microsoft will not cause more damage than they repair by acting in this way or what should happen if they do.