The Amazon Alexa Eavesdropping Nightmare Came True
gizmodo.com
gizmodo.com
Also, the original has a better title & discussion. This title is clickbaity.
I find it hard to believe this was a one-time mistake.
This is not one of the dangers of the GDPR, it's a danger of companies keeping sensitive user data with them forever when they clearly are incapable of being good stewards of it (and no, you don't deserve to be called good stewards if you have even one leak).
Perhaps, just perhaps, this will incentivize companies to have strict data expiry policies (at the very least), but I am not holding my breath.