I don't think A-levels results tell you much on their own.
The people on my doctorate programme that struggled the most were the students who had obtained straight As at A-level. They just thought working harder and harder and memorising more and more was the answer. Whereas academics beyond A-level, and certainly beyond undergrad level, requires more natural intellect, abstract thought and creativity.
A's, and even A*'s at GCSE and A-level can be obtained by the most people with the right parental support (in some cases, 'pushing'), sometimes tutors, a little privilege and a lot of effort. That's fantastic news if the person themself wants to go into a career where those A-levels and the effort involved paid off.
Personally, for my children, we will think about what THEY want in their future, what grades they need, how much they enjoy studying etc.. and go from there. I will always reassure them, that they are smart cookies! Just because someone else gets a higher grade doesn't mean they r more intelligent!
I think if you get 4 As because you LOVE studying, find learning naturally easy, didn't need tutors or small class sizes to give you a hand up, and will go on to continue studying and reading about the subject matter for fun in your free time after exams, then crack on! Those 4 A's are worth it!!
If however, those 4 A*s are the results of extra help, tutors, parental pushing, too much hard work, you didn't enjoy studying and hate learning now you've completed those A-levels, then you could question why you did it and whether it was worth it!