I would be interested to know what high-impact journals you have seen dedications in, because it would be quite foreign in all of the ones that I have encountered.
In my experience, dedications almost always only appear in stand-alone works, such as books and theses, or an explicitly dedicated collection such as a Festschrift, rather than in individual articles of a conference or journal.
There are exceptions, but they are unusual, and I would expect many journals to reject a dedication as "not complying with prescribed format" unless it is buried in the acknowledgements section.