Ask HN: Can Spamming Help?

I was recently approached by a data selling company with Data Guarantee Terms:

  85%+ Email Deliverability

  Hard bounces of more than 15% will be replaced with new contacts.

  Not a single duplicate contact.

  Each contact will come with permission based GDPR and CAN SPAM act,

  Contacts will be for your unlimited usage.

A couple of months back, I launched extracttable.com with a post on Hacker News, a week later on Reddit and answered under 10 questions on Quora. My usual nonpaying user traffic comes from Quora and "direct" (as what shown on Google Analytics), the paid clients were from Quora and HN. Looking into the client base, as expected, 80% of them are combined from Data Engineers/Analysts/Scientists and Python developers. So, I was tempted and responded to them to check the last 3 years PyCon conference users filtered by targetted Job titles. While the price they quoted was ranging between 5-10 cents for the 60K user list, I'm just wondering to see if anyone were successful in this approach.