my prediction is to be 2 trillion dollars. it would go much higher but there are too many outside factors.(mostly bad influencers). it is a brand new technology that changes game right from the start. the biggest factor is integrating this to real life use. which makes it to grow slower.
2 trillion dollars is a possibility. There is no exaggeration in it. Once bitcoin will start increasing, most probably many altcoins will do the same like they usually do. But still this will be a very small one as compare to other markets.
This is the reason why investing in this market can make us millionaire within few years. It has a lot of room to grow. This present dump is making some people insecure but this is just a temporary time.