There have been some pretty big data breaches recently and these have been made available.
In January 2019, the data breach dubbed 'Collection #1' (see: https://www.troyhunt.com/the-773-million-record-collection-1-data-reach/) was made available for all hackers, this breach consisted of millions upon millions of emails and passwords from various sources and breaches in the past. Most likely, most of you getting these emails have probably had their emails compromised and made available.
So like the post says: 2FA and unique passwords for everything.
You will largely be untouchable with 5 minutes of time to really flesh out the security on your account (in fact whenever you make a new account for something, this should be the first thing that you do.)