That's the thing though: OP said they always tried to be grateful that someone even considered to buy them anything at all. The problem is that OP's parents apparently mistook this as them being fine with anything, so they got OP paper and their sibling an Apple product.

Sure, people can have different tastes. Some prefer more complex items that may cost more, some prefer experiences over materialism, and some might simple enjoy just having some company, but OP's parents should have known that showing that level of outright favoritism and causing such an imbalance would have consequences even with the most gracious of people.

At the end of the day, there's a reason we have the saying "squeaky wheel gets the grease", and in OP's case, it sounds like they felt their wheel had been purposefully neglected this time. In theory, price tags shouldn't tear anyone apart, but they just might when that rift is caused by a total lack of consideration.