There is a cultural element, and I've worked with candidates using longer form CVs to shorten them to the preferred US length. It's part formatting, part redund

There is a cultural element, and I've worked with candidates using longer form CVs to shorten them to the preferred US length. It's part formatting, part redundancy, and usually just sharing more information than is necessary. The resume doesn't need to include everything you did. It's a highlight reel, not a bio. You don't need to list every responsibility or even every accomplishment. If I forced you to tell me your background in one page, you'd be able to do it if you have any sense as to what is most impressive, what is important, and what isn't. The reason your resume is four pages is that it's acceptable where you are. I once reduced a 26 page resume to a couple pages for a non-US client. It's usually just triage and deleting, some sentence "refactoring", and formatting. Not too tough, as long as my client doesn't have too much emotional attachment to every detail from their career.