For my own understanding, is the issue with robocalling the same with the issues of spam emails or arbitrary DDOS attacks? In the guise that they look "legitima

For my own understanding, is the issue with robocalling the same with the issues of spam emails or arbitrary DDOS attacks? In the guise that they look "legitimate", but are "malicious" and any attempt to identify the original source is difficult due to multiple proxies masking the origin?