Not all projects are suitable HODL.
I am agreed on this part that holding for all projects is not suitable, many a project can turn into scam and also many project might be delisted and for the delisting the price of the coin can be down and even the price of the coin can be 0.
There is more 2000 different coin and token in market and its true that not all project are suitable HODL. Many exchangers delisted the project from market because many reason and one of that reason is the developers team no longer active or daily transaction volume very low. Better choose altcoin with big daily volume and the developers team always communicate with community