I'd say it is possible because everything in this market is kinda hard to predict after all. The main factor that could bring Bitcoin in that amount of market cap is a massive adaptation. Currently, we large institutions are now venturing into Bitcoin and this brings a lot of positive impact in the market especially in making it firm and stronger. If these large institutional investors continue to enter the market the rest will follow starting from small retailers up to large companies, by that time expect that the market cap will increase and so for the Bitcoin's value. $200 trillion is feasible however it will take a lot of time and effort.