I think Belgium is pretty much out of the question here. They will qualify for the next round 99% as they are always able to switch gears considering the overall quality of their squad. In most cases Croatia is also going to the next round in this group. Canada has had rather weak performances recently so I don't think they can just change gears and play on a totally different level. That's why it will eventually come down to whether or not Croatia is able to show a realistically positive performance or whether they might have a bad day or be unlucky against Canada. Morocco is a bit unknown to me, but I just noticed they had some strong performances in friendlies against Chile and Paraguay.
The favourite indeed belongs to Belgium and Croatia but in my opinion Morocco cannot be underestimate because some people thought the current squad is one of the best generation for Morocco team and at their squad Morocco have several players who played at big teams in europa such as Achraf Hakimi from PSG, Noussair Mazraoui from Bayern Munich and Chelsea player Hakim Ziyech so these players were familiar with European football style and with their experience i am sure they can bringing Morocco becomes an dark horses team who possibly can makes strong teams such as Belgium or Croatia slipped
These are very good examples you brought up and these types of players can push the rest of the squad by a lot! It has often been the case that African teams delivered amazing fights against other teams from all over the world.
People are looking at names too much at times. Everyone who has been into sports knows that the prestige of a tournament (and the World Cup is the maximum) pushes the boundaries of every single player. Also the fact that soccer became more and more international, popular and competitive led to many countries improve a lot because the new generation there started to recognize the role of world soccer and then they started to train harder as well. Concepts can be copied, information is easier to be gathered.
Morocco is an interesting opponent because they have some excellent people on the team who can lead their team and give opponents a hard time.