The tags are intended to guide the crawler to achieve the "best fitting" content for the respective region.

These will "not" increase your SERP position. Though these are best-practice mechanics, that definitely increase your user's experience coming from SEs.

Additionally, you then have better control over the content you "know" will be served to the right user coming from search engines. Hence you can display custom content respective to the user's origin.

Pretty cool, right. Regarding you could serve different lead-magnets with knowing the right audience will see them.