why is SAT easier in america in comparison to UK A levels

I’m from the UK and I’ve just realised how different tests are in each country. SATs are multiple choice in the US, while in the UK A level (determines university acceptance) are not (but some have small sections).
I want to know your thoughts on this, and why not even view the papers:

here is where you can find the A level maths papers (there are 3 maths papers to complete the course): https://mathsmadeeasy.co.uk/a-level-maths-revision/edexcel-past-papers/

and A level chemistry: https://revisionscience.com/a2-level-level-revision/chemistry-level-revision/chemistry-level-past-papers/ocr-level-chemistry-past-papers

P.S. dont hurt me, I just want to hear your opinion on this if youve check the papers out!

You are not comparing like to like. Advanced Placement tests (APs) are the closest to A Levels, although I would agree that these are not at the same level. This is because of the different school systems: in the UK you study depth over breadth - 3-4 A levels in depth over 2 years. American students can take many APs, some of which are harder than others, but often have up to 12 (or more!) throughout the course of 4 years of High School. An AP course can last a semester, not 2 years. Neither is wrong, because they are feeding into different college systems, where that breadth continues for the first couple of years of degree level work in the US.