Modern apples have been bred to be much sweeter and more palatable than they originally were, like many other fruits and plants (e.g. bananas, carrots). While these still retain micronutrients, don’t expect eating them to ‘improve’ your health. They can be consumed in moderation as part of a healthy diet, and are likely much more healthy than ultra processed foods.
If your goal is a lose weight, or you are diabetic, they can still be problematic. Consider less sweet fruits (berries are generally considered the most healthy) or avoiding fruit all together.
Among fruits, apple isn’t a great offer High in fructose, low in fiber and vitamins.
It is a good alternative for sugar cravings when you’re used to junk food though.
But for fruit, look for a better one like kiwis, red fruits and berries or citrines.
If you’re concerned that an apple might be too high in sugar, then definitely eat something else. Otherwise, if you’re not concerned with your diet or losing weight, then eat how many you’d like.