Let's assume this is true, and see what that means: The last 4 Blocks processed 1603 + 1935 + 1047 + 1799 transactions. I'll take this as average: 1596 transactions every 10 minutes. That gives 229,824 transactions per day.
Now let's assume the best-case scenario, in which transactions are evenly spread out between users. That means these 6.5 million users each make 1 transaction in 28 days.
This is of course not realistic: active users make much more transactions, which means the large majority of less-active users take manu months between transactions. The assumption of 61 times more users by 2030 would lead to 1 transaction per user in 5 years at current block size.

Is it realistic to call Person X a Bitcoin user, if he made 1 transaction in 2016? I don't think so. I traveled by train once in 2016, that doesn't make me a train user.
The 50-fold increase in users shows the scaling problem again: prices can't grow as long as users can't make more transactions.

Now back to the catchy topic title: if this is his expectation, did he invest most of his wealth in Bitcoin? The article doesn't mention anything about his own personal holdings.