I joined Uber SRE about 18 months ago coming from a startup where I thought I was busy. So I have some reference points.
Honest take:
The good. Uber operates serious infrastructure at genuine scale. If you want to work on real distributed systems problems, reliability at a level that most companies never touch, it's legitimately interesting. The SRE org in particular has gotten better about on-call runbooks and postmortems. The tooling is solid. I've learned more in 18 months here than in 3 years at my last place.
The not-so-good. The company runs lean in ways that are sometimes exciting and sometimes exhausting. Uber went through significant layoffs in 2022-2023 and the headcount never fully recovered in some orgs. My team does work that used to be done by a team 40% larger. That math shows up as: more on-call rotations per person, slower background work, and the occasional Sunday Slack message that isn't really optional.
On-call specifically: my rotation is every 5 weeks. Each on-call week is genuinely variable. Some weeks it's quiet. Some weeks you're getting paged at 2am and writing a P1 postmortem by 7am. The org has improved tooling and escalation paths but you should go in clear-eyed that SRE at Uber is a real on-call org.
Culture. Post-Kalanick the cultural reset is real. The explicit 'Be an Owner' and 'Big Bold Bets' values have some teeth. My manager is good. I've had no harassment experiences and have not witnessed the things you read about from the 2016-2018 era. It's a different company.
WLB for IC SWE on a product team (not SRE) sounds better than my experience. Friends on Rides or Eats product teams describe something closer to a 45-50 hour week with reasonable expectations.
Bottom line: not a 9-to-5, not a death march. Depends heavily on team and org.