Who will mine the last Bitcoin?
This is a quite interesting question and the answer is simple:
No one, because when the last Bitcoin is supposed to be mined in 2140
1. Humanity doesn’t exist anymore (30% chance)
2. Blockchain has been replaced by something else, maybe inter-concious communication or telepathy through brain wave communication devices (90%)
3. Bitcoin has long been replaced by a different blockchain and disappears into insignificance (80% chance)
4. Bitcoin isn’t using PoW anymore or has increased their supply limit. This will happen anyway within the next 10–20 years most likely (60% chance).
If we go by these estimates, this gives us an overall chance of (1–0.3) * (1–0.9) * (1–0.8) *(1- 0.6) = 0.84% for someone actually mining the last Bitcoin, a very tiny chance.
Keep in mind that point 3. and 4. will most likely already happen within the next 10–20 years.