Will this actually end gender-based violence? Sadly, I'm sure it won't; that will require, in my opinion, an upheaval in everything from early education to media practices (or a complete change in human nature). Will it help? Actually, I think it might.
If you're seriously interested, I urge you to skip the one-page web summaries and browse around in the original report. Annex 4, starting on page 74, might be a good place to start: it catalogs the many, many federal actions and initiatives that touch on this subject. Yes, most of them predate this action plan. But by pulling everything together under a single umbrella, the administration is directing attention to the whole as well as the parts.
I'm no huge fan of politicians of any stripe. But given the US government is very likely going to outlive me, I'd just as soon as much as possible of it was focused on making things better.