$10,000 is too high a prediction. Don't get your hopes too high guys, let's hope for $1000 by 2020.
Do not forget that altcoins are there as well... there is competition.
$10.000 might be too high for 2018 but definitely not too high in general.
And $1000 in 2020 is very very conservative prediction.I think we will be higher than that.
Regarding altcoins they are mostly by traders to increase their Bitcoin stash if they are good at it.Also Altcoins never will replace Bitcoin as long as there will be no real serious issue with Bitcoin than can not be fixed.
However I believe a good hand full of alts will find a niche with some nice value.But finding them is like searching for the needle in the haystack.