There are indeed a lot of room left to see about what is going to happen, but i'm not sure and i would love to know about your opinions. Bitcoin dominance is indeed high right now, but how do you think it will be around 20 years in the future ?
i think this must be in speculation section that you can find here
https://bitcointalk.org/index.php?board=57.0better transfer this for more appropriate answers.
anyway for me?the domination of bitcoin may have a chance to change in that 20 years because there will be another currencies that may prove its capacity to serve more the cryptonians and maybe the supporters will change hands when the time comes.