The Bus Factor was indeed an issue before LLMs, and in fact it's a jargon term that has been in use since forever.
What TFA is arguing is that never before we had a trend towards Bus Factor zero. Before, the worst was often 1 (occasionally zero, of course, but now TFA argues we're aiming for zero whether we're aware or not).
True, but when the bus factor is 1, it might as well be zero -- soon you end up with employees (or contractors) who legitimately want more compensation realizing their critical nature. I totally sympathize from the employee's perspective, esp if the 1-factor means they cannot take holiday. Really, it is the company's job to control the bus factor (LLM or human) -- it is good for both the employee and company in the long run.
Agreed, it's the company's job to control the Bus Factor, that's a given. I think TFA's author worries that instead of controlling it, we're now aiming for zero (the worst possible factor).
A Bus Factor of 1 has always been construed as high risk; that's why the term exists after all. Companies sometimes mitigate it, sometimes not, but in general they are vaguely aware it's a risk.
A Bus Factor of 0, especially as an implicit goal, seems doubly worrisome! Now it's a goal rather than a warning sign.
When I was an architect for startups between 2016-2020 doing mostly green field development using new to the company AWS technologies, I made damn sure that any knowledge was disseminated so I could both take a vacation without being interrupted and I could “put myself out of a job”.
I considered it a success when I realized a company doesn’t need me anymore and I can move on and talk about what I did at my next interview in STAR format.
Agree, and also, promotion is hard if you are too tied to a specific system. Diagonal cross-department promotion becomes especially hard if you are a single point of failure.
But a Bus Factor of 1 has always been considered high risk. Sometimes companies take the risk, but that's a different issue.
This is precisely why the term "Bus Factor" was invented: to point out when it's 1, because it's both high risk to the company and unfair to the dev that cannot go on vacation or extended time off.
What TFA is arguing is that never before we had a trend towards Bus Factor zero. Before, the worst was often 1 (occasionally zero, of course, but now TFA argues we're aiming for zero whether we're aware or not).