The contest topic itself is helpful to math learners ~ but domestic competitions pay more attention to the extra points when entering higher schools, while ignoring the interest orientation of math learners themselves in math learning ~ You can think that it is a good idea to exercise your thinking ability by doing contest topics. First of all, mathematical thinking and holistic thinking are two interrelated processes, especially when people are doing logical things, mathematical thinking plays an important role! There are also competitions to cultivate people's thinking. As for whether what you said is helpful to high school study, my answer is yes. At least in thinking, you stand higher than others, but simply from the perspective of learning content may not help much. Even if you don't do competition questions, you can reach a good height as long as you can study hard!

Finally, my advice to you is, don't blindly follow the footsteps of people around you, ask yourself whether you really like math or are interested in contest questions, otherwise it is not worth the loss to do contest questions for the sake of doing contest questions ~ I hope you can go further and more steadily on the road of math!