Who I am is not important. These ideas will be. Please read fully and digest before forming knee-jerk opinions based on anything other than presented content. There will be no TLDR for this reason.
Bitcoin fills an important space in the ecosystem of decentralized digital currency as it exists a store of value for eventually all other digital currency use cases to have value measured against. It can exist as a reserve currency for this space. It's function can be compared to gold in this way. We have the saying that built bitcoin's user participation and the narrative of "come for speculation, stay for digital gold" which is incredibly effective marketing and has so far been a brilliant design. There is a fundamental flaw that has been introduced as an attempt to solve a problem in an elegant way. It succeeds in doing so and also introduces a new problem set that we have not seen the effect of yet as we have not reached the point where it will become apparent.
It is important to the life of Bitcoin that this flaw is able to be addressed in a manner that is much faster than the process for implementing change allows so that in the moment where trust in it's system is undermined adaption is fast enough to not be overtaken by development of a new product which would cause trust to have to be rebuilt from the ground up either in bitcoin as it changes or in the new product that addresses this and that would be a battle. It is also important that the process for change not be shortcut or undermined as that is also damaging to trust. Therefor I would begin this process before it is apparent that it has become necessary so the process can be followed through fully and this change still implemented in a manner that is timely relative to the understanding of this issue becoming uniform.
This issue is the twenty-one million coin hard cap on the creation of bitcoin. The cap exists to set inflation rate to zero which presumably and seemingly solves issues around centralization via regulation of supply through adjustment of the rate of inflation. It also provides for a predictable economic model. It is somewhat elegant in this way. It introduces two core issues for the development of bitcoin's ecosystem at scale.
The first is that bitcoin is designed for the mining reward to be an incentive for proper network behavior. What happens when there are no more coins left to mine? Who do we trust to validate blocks with no reward incentive? It is possible that people will continue to do this just to maintain the network because they believe in it's mission. It is better to trust this function to the system than to the whims of people.
The Second is in the comparison to gold. Gold has existed for a very long time and still has not achieved full market penetration. Bitcoin is on this track, and at an accelerated rate, but as it continues to gain market share as a store of value this rate decelerates as it approaches users that are more difficult to acquire. This process takes a long time (for reference from a technology perspective even the internet only has around 50% global penetration as of 2019. The internet is bitcoin's vehicle and it has had a few more decades to mature). The viral loop baked into bitcoin does not last long enough to achieve this and eventually stops being an incentive to new users as well. This is again because of the twenty-one million coin hard cap. Gold has this naturally diminishing supply that does not perceivably ever reach zero and so it's own naturally occurring viral loop as it becomes more difficult to find and mine lasts much longer than bitcoins will. We have not yet seen the result of bitcoin hitting this wall. It may well survive as is (I find this less likely) but it should be ready to adapt if it becomes apparent that it will not. There is good news.
Bitcoin also has a naturally diminishing supply built in and as it turns out the problems that the hard cap is meant to solve are actually naturally solved by the design of the mining protocol itself and the cap is essentially irrelevant thanks to this. The mining difficulty doubling every four years and bitcoin becoming increasingly more difficult to mine based on user acquisition actually provides a natural curve where the limit of inflation approaches zero on it's own so it does not need to be artificially defined to reach zero. It is always heading there. This means a few important things.
Even without the limit, the level of inflation is still completely defined, predictable, and outside the hands of human intervention. It also still always approaches zero as more coins get printed and the rate of mining decreases so the value of bitcoin continues to rise. It solves all of the same problems as the arbitrary twenty-one million cap without having a human define it. This allows bitcoin to compare more directly to gold as the limit constantly approaches zero but is effectively still unknown in gold's case. In bitcoin's case the limit would be defined by human and technological capacity to solve for the difficulty as it increased so it would also effectively be unknown rather than infinite at any given point, while being infinitely scale-able rather than just very large (given our capacity to improve the efficiency of our technology to interact with the protocol over time).
We have not seen how this will play out in any of bitcoin's cycles because it is a fundamentally different thing to become zero than to just decrease. I understand some coins have been created that have made exactly and only this change. Those coins do not compare to bitcoin in many other ways that are outside the hands of their developers so they are largely irrelevant in understanding this. Have we ever communally understood why this change is necessary? I believe it would be best for everyone if it were bitcoin that evolves and not some other coin that eventually forces a reset when we are confronted with this problem (when the mining supply dries up).
I call this the final battle not because it will be the last one on a timeline but because it will be the last one that will be relevant to bitcoin's continued life and health outside of the complete destruction of society as we know it.