SmartmanApps

You don’t necessarily have to do parentheses first

Yes, you do necessarily have to do it first

What matters is that the things inside the parentheses are a group that you can’t break apart

And outside, and you must do them first. You haven't finished Brackets until you have 5(8-5)=15.

10÷2+3-2*(2+1) you can do the division first

only because you've separated that part with a plus sign

then multiplications

There aren't any, only Addition and Brackets (and Subtraction inside Brackets)

I mean, there are very few ambiguous cases

There are precisely none which are ambiguous

so it would be clearer

That's because it's already clear as is, as per the rules of Maths.

I think someone told me that order of operations is like a natural law

It's a natural consequence of the definitions of the operators. e.g. Multiplication is shorthand for repeated Addition - 2x3=2+2+2 - so if you don't do it before addition you end up with wrong answers. The order of operations rules is in fact just breaking everything down into Addition and Subtraction and then solving from there.

not a convention

There are some conventions, like left to right, but in that case that's only because students tend to make mistakes with signs when they don't go from left to right, so it's there to preserve teachers sanity.

We created math

We discovered it. There are even multiple animals who know how to count

that there was a multiplication there since it isn’t explicit

There isn't a Multiplication there, only Addition and Brackets, and Subtraction inside Brackets. It's never Multiplication unless there is a Multiplication sign.

Remember that multiplication goes first

Remember Brackets are solved first - there is no Multiplication

so it’s: 2+5(8-5) = 2+5*3

No, so it’s: 2+5(8-5) = 2+(5x8-5x3), a(b+c)=(ab+ac).

It didn’t make sense to me to multiply the 3 & the 5 with zero consideration for the “2”

That's what the order of operations rules say to do. 2 doesn't come into it until you get down to the Addition step.

just write it better

It's written like that in Maths textbooks. i.e. there's nothing wrong with it.

Writing it like (8+5)5+2 =17 also makes perfect sense

Actually that's invalid syntax. Imagine if it was (8-5)-5 and you see why.

posting out of order math problems

There's no such thing, only people who remember the rules of Maths and people who don't

I literally fixed the equation so that it would be less confusing to people

No you didn't. You wrote something that is mathematically invalid.