https://en.wikipedia.org/wiki/Order_of_operations

isn’t a Maths textbook

In mathematics and computer programming, the order of operations is a collection of conventions

and rules 🙄 Haven’t even got past the first sentence you quoted and it’s already wrong

These conventions

Rules

but some programming languages and calculators

May disobey the rules and give wrong answers, like Texas Instruments calculators

With math, you can invent your own notation if you like

Yep, but you cannot invent your own rules 🙄

This is done often.

No it isn’t.

And if it makes sense, you can also change the order of operation

No you can’t, or you get wrong answers, like Texas Instruments calculators

The notation you learn in school is just a common one, but other notations are equally valid and can be useful

But the rules are universal. You seem to be confusing notation with the rules

Therefore this kind of question is not a pure math question

Yes it is

what kind of conventions or notations people want to use

We can see for ourselves quite clearly what notation they have used. There’s no mystery or debate about it

The context is what allows the math question to have a single answer

The rules of Maths is what gives it a single answer - that’s what they’re for! 😂

The rules of math itself are much more fundamental and they don’t care about how people decided to write formulas down.

Yep, one of which is The Distributive Law, a(b+c)=(ab+ac).