I find these kinds of rationalizations to be hilarious. Bitcoin will succeed on it's own merits, not because "zomg wall street/putin/buffet/gates/justin bieber" are going to discover bitcoin and invest in it.
I've witnessed some crazy pumps in pennystock land but nothing as outrageous as bitcoin land. This idea of Putin moving his $40B into BTC is just nuts.
Usually when someone is said to be worth $40B. It's probably the net of their assets. Not a pile of cash sitting in a bank somewhere. It's probably distributed in stocks, bonds, real estates, cash. If someone has $40B in the first place then they most likely know a thing or two about finance