Man this is confusing.
I'd personally be most interested in how much gold one could make in a year starting from scratch, with no plat. Like level 1.
It depends on the dedication of the player. I'm assuming this is a person playing normally? Levelling up, going to bosses, buying gear, etc. You can make a decent amount of gold by farming and bossing...though you would be losing gold when you buy gear as well. I think the main decider is how the player dedicated their time. If they can spend 15 hours a day playing the game, and split their time between leveling, bossing, farming, merching etc. They could make a pretty huge sum of gold. Someone who is limited to playing only an hour or 2 a day would struggle more.
I think it all comes down to player dedication (with a decent amount of RNG thrown in for double gold when farming, lucky boss drops that can be resold highly, etc). Someone who really sets their mind on making gold and has the time for it will do well. If someone isn't really interested in getting as much gold as possible, and simply wants to enjoy the game, they will get less gold overall.
So my short answer to your question: there really is no limit (though 100m+ seems highly unlikely)...it depends on RNG and how dedicated the player is.
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