As Henry George (American Economist) once pointed out:
Man is the only animal whose desires increase as they are fed; the only animal that is never satisfied.
This goes to say that whenever you aim for something that you wish deeply (for example having a well paid job) once you get that well paid job you'll have lots of joy and hapiness in the first months, perhaps in the first years ... But after a while you'll get used to that well paying job and you'll want more because that one doesn't satisfy your needs for now - This shows the nature of man and it's continuos quest to never be satisfied with what it has and to "consume" itself to pursue their desires until they reach them , only for pursuing bigger ones once they got used to it. As a side note Budism basically tries to "counter" this urge with their concept of Nirvana[2] (a very brief and short description):
nirvana nērvä´nə [key], in Buddhism, Jainism, and Hinduism, a state of supreme liberation and bliss, contrasted to samsara or bondage in the repeating cycle of death and rebirth. The word in Sanskrit refers to the going out of a flame once its fuel has been consumed; it thus suggests both the end of suffering and the cessation of desires that perpetuate bondage.(...)
This small introduction was only made to sustain my answer to your question OP : I think that no matter wealth that one has, one will always want to have more of it - and our own desire will make us search for a constant feeling of accomplishment/joy followed by adaptation of those same feelings.
As a closing remark I think that if we were all millionaires perhaps what would change would be the investment size that we would make (it would also depend on how much we trust BTC as well) - I would say that perhaps instead of buying 100, 200, 300 USD of BTC they would go for 5K, 10K, 15K ... While holding for the amount of time that they believed their investment would pay off - after all, we are talking about millionaires and bilionaires, I'm sure they are fully aware how can they actually grow their fortune
[1]
https://www.brainyquote.com/quotes/henry_george_3911908[2]
https://www.infoplease.com/encyclopedia/religion/eastern/buddhism/nirvana