Good for you d.
When looking at the price of anything, you have to understand the factors that are responsible for that pricing. Both now, and in the dotcom, leverage was very high. Everybody is talking about price supports today, and they are right.
In dotcom, ratios and prices hit a certain level, then crashed. Now they are at similar levels. The markets do not exist in a vacuum, as assets and investments they are but few offerings in a broader marketplace.
In short, there may be some intrinsic maximum price level that can be sustained, given certain assumptions about especially currencies.
If those stocks were to go up the same amount by 25 years from now, my bet would be that EITHER: 1) they would rise from a lower level, which would mean a deep correction before that rise began, or 2) roughly equivalent currency devaluation during that period, or increased taxation that results in a relatively static "value".
From my perspective, the important thing at the moment is to have liquidity so that one can respond rapidly if the opportunity arises.