If there's no "self', and "I am" is just a "flow" or "mix" of information (dharma, karma, etc.); and if, when I die, "I" (body, illusory self, soul) will die but this informational flow will keep going into another being, and then I no longer exist, think, feel or I will be different being, so this being will be living but not me, then why should I care about his life if I will no longer exist?
There are truths that are deep and hard to understand.
What are these truths?
You are everywhere.
You are everything.
You are deathless.
You are neither perfection, nor imperfection, nor anything in between.
That's pure bliss.
That's the "real you".
In order to be this "real you", your future "I"ies must cease to become.
In complete cessation of becoming, future "I"ies will not be born.
When "I" is not born, this "real you" remains.
And what is it that remains?
Undefined is the answer.
As soon as you give an answer, "I" arises and this "real you" becomes tainted with "I".
And what is the "I"?
It's limited with a body.
It's limited in space.
It's limited with death.
It's limited with imperfections.
That's the "I".
It's because of these truths that your current "I" should strive to realize these truths so that no future "I"ies will ever arise.
Or is it that there is a some kind of eternal selfless "self", the "watcher", that experiences this (and the next) existence and can think, feel?
The "real self" is the eternal selfless "self". The "watching", experiences, existence, senses, knowledge and everything else arise because of ignorance - not knowing this "real self".
How does this "informational flow" ("soul"), a conglomerate of functions, get into someone's body?
As long as "I" arises, the view that a "soul" gets into a body can arise.
Does a "soul" get into a body?
Given the right conditions, it does.
Does a "soul" not get into a body?
Given the right conditions, it does not.
Does a "soul" exist?
Given the right conditions, it exists.
Does a "soul" not exist?
Given the right conditions, it does not exist.
Does a "soul" exist and not exist?
Given the right conditions, it does exist and does not exist.
...
There are many views. Neither of them lead to nirvana.
The letting go of all views is the path towards nirvana.
Is nirvana an "informational" suicide?
There is neither suicide nor no suicide nor both nor not both in nirvana.
And if the reincarnation is like an ocean water been poured into glasses and back, and there's no core self and individuality is just a mix of informational patters, then maybe it's pointless to try to stop existance, to go to nirvana, because someone will always remain here.
There are many views:
Nobody is here.
Somebody is here.
Nobody remains here.
Somebody remains here.
There are no "I"ies or "selfs" or "souls".
There are "I"ies or "selfs" or "souls".
...
All views, given the right conditions, can be true or not true or both.
All these views are just your "real you" tainted with ignorance.
The letting go of all views is the path towards nirvana.
And if this Samsara is eternal then there can be eternal number of Buddhas, beings and they will be trying to get out of this Samsara eternally, then all their actions are pointless.
Samsara and its beings can be eternal or not eternal or both. All these views, given the right conditions, are correct.
No action is pointless. They all lead to nirvana.
Every action has good, bad or neutral consequences.
Every consequence, can give rise to new knowledge.
Every future "I" is reborn based on the knowledge the current "I" has.
It's because of these truths that every "I", on a long term, consistently increases his knowledge.
When knowledge increases enough, the truths are realized and future births are stopped.
No action is pointless. They all lead to nirvana.