Pros
If you have a good manager, your life will be easy. Codebases are generally well maintained, the business itself is interesting, teammates are talented and easy to work with. Truly a great working environment and day-to-day. Have never felt pressured about taking too much PTO, and I have a great work/life balance. But again, this heavily depends on your team. Note this is heavily scoped to "work as a software engineer". Teams are constantly getting new designers/PMs/QA engineers, who then get shared across multiple teams, and tend to not stay too long on one team, leading to a sense that no one has the full picture of what's going on on a team.
Cons
"The mission" is constantly used to justify problems in the company. Low compensation and raises has led to high attrition rates across departments. CEO will frequently, publicly thank employees for "burning the midnight oil". The CEO waffles on whether employees will be required to come back into the office, leading to everyone worrying they'll be fired if they want to work remote. This has tanked morale (in my department at least), immediately after a round of low raises. Feedback disappears into a "you talk to your manager, they talk to their manager, who talks to their manager ..." vacuum. Very hierarchical.