There are other factors like the alternatives and their risks over that period (e.g. the S&P has nearly doubled in nominal value over the last two years and there are many high yield bonds of questionable risk) but I'd guess 0.1% is a fair estimate of what the market considers the likelihood of BTC having roughly the current market cap of gold in 10 years.

Of course, the market is made almost entirely of traders who have no way to accurately evaluate the risk (if they could, we wouldn't have bubbles). Even understanding Bitcoin itself requires a good understanding of computer science and economics - what % of traders have a firm grasp of both? And who can predict the global economic climate over the next decade or what financial regulation and monetary policies will be chosen? Anyone that could might easily make more over that period than even this potential 5000x ROI on BTC.