I don't completely agree with that message. I think it would be completely opposite and alts would rise once bitcoin has reached certain threshold. People like to diversify their portfolio and it would be very difficult to put all that in just one bitcoin. There is less reward for those investing.
some altcoins are seen as having high potential. help them not sell it for bitcoin. especially at very cheap prices. it will not provide the same benefits even though we store bitcoin. waiting for the altcoin to grow and having a reasonable price is the best choice.