When one takes a close look at the First Noble Truth, one can see that it leaves out some possibilities which are obviously pleasant and bring happiness: youth, health, life, association with the liked, separation from the disliked, getting what you wish for.
I guess that the idea is that common people are blinded by these allures and can’t see the drawbacks of existence (even though they might be obvious) - therefore they lack overall picture and look only at one side of the coin.
In case of the aggregates the allure of them is that they can bring pleasure. The drawback is that they are unstable and liable to unintended change therefore they can bring suffering.
If one wishes to escape the drawbacks one has to let go the allure aswell - so, let’s toss a coin away