The maximum number of coins is also irrelevant (aside from technical reasons), particularly as mining output scales linearily with the amount of the initial stake. Does it matter if bitcoin has 21,000,000 or 21,000,000,000 coins, if everything is scaled up similarily?
this. Mining output is 0.5x (x = number of ethers bought initially) per year. Linear inflation.
There's no cap, so where is the 1.2 trillion coming from? I think it's probably based on some assumptions (mainly a certain "x" and a certain percentage of coin loss?)
Yes, from the whitepaper:
We also theorize that because coins are always lost over time due to carelessness, death, etc, and coin loss can be modeled as a percentage of the total supply per year, that the total currency supply in circulation will in fact eventually stabilize at a value equal to the annual issuance divided by the loss rate (eg. at a loss rate of 1%, once the supply reaches 100 * (0.5X) then 0.5X will be mined and 0.5X lost every year, creating an equilibrium).