Modern corporations are the best profit maximisers any human has ever seen.

Compared to what?

So: older companies mostly.

Lifespan seems like an irrelevant metric in a discussion about corporate intelligence.

Ceteris paribus, long lifespan helps with generating profit: long-lived corporations accumulate reputational capital, institutional expertise, allows more amortizing of long-term investments, etc.

Death is much less of a significant factor than with humans, since old corporations can be broken up and the pieces sold. It doesn't matter so much if old corporations die when their parts can be usefully recycled. Things like expertise can easily outlast a dead corporation.