As you say, the devil is in the details.
Regulations require paperwork and enforcement will be as spotty as compliance. If, and I suspect it will, it comes down to every boat having to have an A.I.S. transponder installed it will be a major impediment to the budget boater among us - and silly in the extreme. KNowing how politics work in this country a requirement like that would be phased over a decade, and grandfathering would skip 'classic boats' with no power source - in the aggregate making the requirement as useless in reality as it is in theory. Besides your basic 70 mph jet ski loaded with a 50kg explosive can indeed take out a CNG carrier in the harbor quiet nicely while radiating "I'm Susie from jetskirental.com" all day and no amount of paperwork, regulations or regulators can make that risk go away.
Tell me what good 3 inch tall numbers on the side of my boat, a AIS broadcasting "i'm chuckles", a MD State registration sticker and a USCG aux safety inspection will do if Abdul Isaih Mohamed (pardon the sterotype) decides to board me and use my boat as as a ramming platform for the aforementioned CNG carrier in the Baltimore harbor?
Nothing. Worse than nothing, all the stickers and stuff do give the DHS a false sense of security and provide just enough confusion to delay a trigger finger. BTW you can fake said stickers good enough for the average 100 foot away glance with the average child's box of crayons. National security foiled with a 2 dollar box of crayons.
What does keep that from happening? The fact that as a ramming or attack platform my 7.2 knots of powered boat speed is ridiculous.
Now banning all high speed wake producing stink and noise producers would be a good idea

. Developing and leveraging that into existence may put a strain on public relations.