You can take advantage the collapse but this depends on why it's happening. If it's because of the normal bearish season due to Bitcoin is plunging and alts are following, then you can buy alts that you like to invest in for cheaper price. Choose the one with potential and worthy to hold.

But if you're pertaining to alts plunging because of the dump of many investors because it is a pump and dump coin, then think carefully. Ask yourself if it is good to buy while others are dumping. Reseach if it has a utility and sustainable. If the answer is no, then stay away if you want to lose your money.