Sooner or later, BTC will reach those levels where it will either consolidate for a long time or go into correction, and investors will most likely start looking at alts at that moment.
There are investors who have no chart knowledge and may likely not notice when BTC starts consolidating. The lack of that knowledge may actually save them from making some sorts of investment mistakes because with people expecting altcoins to have a new ATH, they may be prompted into investing without research or investing in too many altcoins, a risk they cannot handle.