If you lose 10 software engineers due to the bus factor, the fact that you already are treating engineers fungibly gives you resilience on that front.
The business community wants everybody and everything as replaceable and fungible as possible, to its long-term detriment. That so many see short-term "success" and call it that should be far more appalling than it seems to be.
Take Circuit City, for example, which, when it was already struggling, let go all of its senior sales people on the floor and replaced them with minimum wage. The knowledgeable salespeople was pretty much the only thing going for Circuit City at the time. Customers noticed, responded, and the business fell off a cliff
A couple of times I've landed at a good company, where I figured I could stay for a long time and build something resembling a traditional career. But something invariably changes - the company gets acquired by some MegaCorp, a leadership changeover, your awesome team gets disbanded and scattered, etc... c'est la vie.
Really great team, great project, great codebase, loved a lot of things about it.
Then a leadership change happened. I've got a new job, gave my notice, and hopefully will keep in touch with the people I like here. Very bittersweet time.
that’s just capitalism
Human capital has value and appreciates over the long-term