I’d prefer it if Chult had more keyed locations in the jungle to investigate – in a home game, I’d fill it with ruins and other items of interest – but the random encounter tables do allow you to have something happen as they travel. It’s the first situation that makes the best use of the random encounter tables.
What are the group trying to achieve in the jungle? However, it also depends on the situation. It’s not good with groups who are more interested in the story having sessions of combats that don’t advance the story tends to be frustrating. If you’ve got a group who enjoys a variety of combats, then the random encounter plan can work very well for you. I was very happy when younger to kill them randomly generated monsters.
The problem with this is that it eats up time and can lead to very boring adventures. It’s easy to become distracted by the rules given on the adventure: Roll three times each day to see if an encounter occurs, then determine what it is. You’re likely to become very familiar with it in the early levels of Tomb of Annihilation, as the adventurers search for clues.