Yes, also the parent generation eventually dying off confers survival advantages to the younger generation: fewer old folks consuming resources and providing little value in return.
I'm completely talking out of my ass here, but I suspect systems will tend towards rent seeking/"cheating"/maintaining a status quo/really, just "overfitting" to the environment by making the ecosystem around them dependent on them.
Death ensures resiliency and progress. If we ever actually achieve some form of (pseudo-)immortality, i'd hope that we introduce an "afterlife" which removes the post-mortal from "living" society/ecosystems after s certain point. at most, living society should be able to inspect & affect the post-living system (afterlife), but the post living system should be airgapped from being able to (at least, directly) affect the living one at all. that said, i'd be wary about indirect affects. to die is to not influence. i'm still influenced by the memory/simulacrum of my grand mother who raised me until middle school. thats some degree of affect on my ecosystem, but it isnt what i would call direct.
i suppose there need not be a singular timeout or ecosystem a system is depolyed to, so long as it converges to zero. Heck, not even monotonically nor with a consistent cohort of systems.
Like the Undying Lands in LOTR?
I feel like this hypothetical scenario is contradictory (and, supposing there was engineering behind both this life and an afterlife, is an argument for keeping the two isolated). Data is code, so data collected from the afterlife is potential for "remote execution from the afterlife" (not that humans are computers, but for example traditionalists who were able to directly study the long-dead would act differently than if they had to piece tradition together from scraps of documents - particularly, it would freeze traditions/memes rather than letting them evolve) and therefore death losing its role as the cessation of influence.
This is also why institutions should have a lifetime. Corporations, government entities, all the things that don't have a natural life length really ought to.
As a parent living by my in-laws, I can assure you that, far from providing "little value", raising children without support from grandparents would be severely more difficult. Personally, I see generations trying to be independent of one another as a large factor in making modern childrearing increasing difficult.
And this is aside from the knowledge, and labor that would have been so vital in former times. The old woman spinning and knitting is a historical trope, but when you have to hand make all of your textiles, she becomes quite useful indeed.