Most software engineering and executives jobs have a tenure of three years, and I think culture is definitely preserved for longer than that. However, it's very rarely preserved over decades.

You're citing a classic joke. The experiment doesn't replicate when people tried to test it:

https://www.answers.com/Q/Did_the_monkey_banana_and_water_sp...

So if in the company the average tenure is 3 years, then the culture is what has been practiced in the last 9 years... Even if the company itself is 20 years old.

In another company with tenures of average 5 years then company culture is what has been going on the last 15 years.

What do you think? Does this idea mire closely match your experience?

I can't say I was intimately familiar, but at the level of reading books and trade press as good enough for the statements I'm making.

You don't need a lot of depth of knowledge to know when a culture completely changed. If you go outside and see a Toyota Camry and another Toyota Camry a week later, you can't tell whether the car is the same one. On the other hand, if one day, it's a Porsche, and the next week, and 18-wheeler, you can be pretty sure something changed....

I would agree for most companies and it's probably true for Microsoft but that doesn't really apply to Google. Google is 23 years old. 20 years ago the people who wanted to work at Google were looking for a young fast-growing company shaking things up with its search engine, a heavy focus in engineering and opportunites everywhere. Nowadays, the people who want to work at Google want to work for one of the most prestigious tech company. That tends to attract a completely different kind of person.

Also that last point probably only work if the punishment is incredibly big, and I doubt something like that exists for the scale MS operates at.

The Ship of Theseus is a question about the nature of identity, not an answer.