Time sequence does not mean causation. My kid got a sunburn this summer and is now in school. The sunburn did not cause him to go to school...
I have used Microstock Plus for almost a year now. Storyblocks is one of my accounts. Neither it, nor any of my other accounts has been hacked since I started using MSP.
OTOH, I HAVE had accounts hacked in the past -- at Shutterstock, Adobe, and one other who I forget right now. In each case, my account was changed to assign my payments to a foreign bank. In each case, I was able to recover before any money was paid (thanks to the email from each agency letting me know there was a change). In each case, I then changed the password to something more secure and unique to that account. No problems since.