It doesn't seem to me that much sophisticated, rather "normal", unless they are omitting some relevant details, it sounds a lot like "Action needed urgently, click here to login to ...".
Could be anything from average phishing or some 0-day that happened to be found by gov employee or phishing email, to "a bunch of men kidnapped target and beat them till they gave them access
Basically applies to every team there is.
Means almost every other time you're sent a link, you have to log in yet again. And man are you sent jira tickets often in tech.
The employee's password was probably passw0rd, and that's being generous for reddit.
It usually involves meticulous research on the target, what and who they work with, and have crafted an email that plausibly looks and sounds like an internal email, that talks about company stuff in company language, mentions coworkers and so on.
Add a note of urgency, make it someone who has discovered something isn't right, there's an urgent technical issue or the company or money is missing from the accounts or something, or perhaps it was dressed up as a memo announcing layoffs at reddit. If it's an urgent "threat" you tend to tunnel vision quite hard.
The result is very far removed from how your typical spam emails tend to look.