> it is a career-ending failure

It depends highly on the field. In history, sure. The point of getting a history PhD is to become a history professor, and you can't do that if you don't get the PhD, and meanwhile history PhDs don't meaningfully open up any other job prospects, so attempting and failing to get a PhD provides negative value.

In CS and many engineering disciplines, there is a long history of people dropping out of PhDs and landing in industry. The industry is therefore much more accustomed to, and therefore accommodating to, people taking this path. Whether it's a maximally efficient use of time is another question, but it's certainly not wasted effort.

But I do agree that it's stressful nonetheless because it still feels like a failure even if it is not actually in reality. I wrote about this when I put down my own PhD journey here [1]. In particular after the control replication (2017) paper, I very nearly quit out of academia entirely despite it being my biggest contribution to the field by far.

[1]: https://elliottslaughter.com/2024/02/legion-paper-history (written without any use of LLMs, for anyone who is wondering)