Spam is a way of life on the Internet
One a persons e-mail address is exposed on the Internet, there are Entities and Persons who harvest this information
Then, they Sell this info to Spammers
There have been some Data Leaks from some companies and personal info like e-mail addresses have been also Harvested and Sold to Spammers
I can say from personal experience that a former ISP had, did have leak and yes a former e-mail address I used would receive a ton of Spam
The Block Sender function does block the specific sender and does move it to the Junk Folder
At least that is working on 3 machines I use
Have only read some Other Contributors who have used this Third Party Application that is setup right - it just works as a Supplement to the Block Sender function
There is a free trail or Paid for arrangement .
https://c-command.com/spamsieve/ ( External Link )