I think other coins will steal some of the thunder away form Bitcoin in the future as some like Ethereum can do more. But I can still see a 25k - 35k Bitcoin in 5 years time.
I think that prediction is low for five years, to me it seems the price could reach that value in one or two years tops, personally I would like for bitcoin to slow down so it gives more time to accumulate bitcoin before it skyrockets but if bitcoin wants to make us rich that soon I do not have a problem with that.
I think it is reasonable predictions. 25k-35k is an ideal figure for sustainable development. Bitcoin should not increase too fast, it will lead to many instabilities.