For me, a more interesting question is that if our bodies can arbitrarily slow down aging by releasing proteins, why wouldn’t they just do that?
Maybe there is some evolutionary trade-off behind it?
Maybe there is some evolutionary trade-off behind it?
But that argument doesn't prevent limited mechanisms, and conditional mechanisms in particular would still be rewarded. Conditional mechanisms provide much more short term adaptability to changing conditions, without damaging the long term species-wide adaptation.
There are intriguing parallels with centrally planned vs market economies.
There's a common theory that for mice, they're unlikely to survive for many years because of predation, so there's not much benefit to preventing aging in later years. Small benefit means any counterbalancing disadvantages (lower vigour?) could outweigh the anti-aging benefit, or that the force of selection is insufficient to overcome random mutations that degrade the anti-aging mechanism, but "that's good enough, no need for more" is not how evolution works.