Yep LastPass has been breached, and perhaps even copies of people's encrypted vaults stolen. Perhaps even some of those were stolen in 2005 such that 16 years later brute force was able to identify at least some of the users who had weak passwords.

The question remains just how long will it take for someone to find out the keys

1 day
2 weeks
4 months?
1 year?
10 years?
100 years?

My personal bet is somewhere in the 70+ year range, though who knows what will happen in the next 70 years :-)