I am half-convinced that this argument that "Gen Z will be poor forever!" is a fear tactic on social media. Not trying to dismiss Apple Fanboy's point, but that's where I see this discussion. I do not see it in real life.
Does "doing well" mean owning a house? My parents did not buy until they were in their late 40s. That's fine. Were they "doing well" before that? Yes. They didn't have their children until their late 30s/early 40s. That's fine. Having a good job... well, my mom taught for almost a decade and didn't like it. That's okay. I really don't understand the pressure. I really don't. Maybe my family is an exception, I have no idea. I sincerely doubt it though. I guess that's one thing I've learned being raised by my parents (and, shout-out to them, because they're absolutely wonderful), is that it's fine to take time.
Besides, "doing well" is deeply personal. Someone else - and more importantly, broader society - cannot dictate what that means for you. If you are happy in your situation, that is the most important thing.
Is retirement harder than it was 50 years ago? Probably. But I am so far away from that, I really don't care.