Put the blame where it really lay's, with the criminals and illegal telemarketers.
The DNC works just fine. It is for telemarketers only and honest business does indeed abide by it. It is the criminals (which includes illegal telemarketers), frauds and scammers that do not. However, the Fed. DNC does not cover some survey's, Political or Charities. You would need to check your states DNC laws to see if these are under your states DNC laws. The fact remains that they are not automatic call blockers though and can not protect you from the calls that are criminal, illegal or fraudulent.
Do consider maybe getting a call blocking device or phone.. You can google them and many are around $60.00 or so.
these calls are increasing and to be honest they all seem to be coming from the same company, card services as they all seem to be using the same format. It rings only three times so as not to trigger the answering machine and if you do answer then there is a delay as the computer that did the calling tries to find someone to take the call. Best advice is that you just don't answer the call if number is not recognized but if you want to have some fun, then anwer and then pretend that you cannot her them. They talk louder and you say Hello louder. Mutter, Damn phone and hang up. I have had some sucess with that