Grade crossings are inherently unsafe at those speeds. It was a known bad design from the start, as the article points out. And several of the deaths were *not" of the type you mention.
Crossing gates should come down 20-30 seconds before the train gets there, pretty much regardless of train speed.
I suppose that the difference may be that, at higher speeds, the train is further away when the gates come down, and people don't realize how soon it's going to get there, and so decide to go around the gates. (And, I suppose, when there is an accident, it's more likely to be fatal because of the speed.) If you meant anything other than those two options, though, I'm not sure why you think that "grade crossings are inherently unsafe at those speeds".
Do they? It seems like Japan recognizes that it's a major safety issue that causes a significant portion of fatalities, and is working hard to eliminate them entirely.
Obviously level crossings are riskier, but comparing the stats in this article to the OP makes it pretty clear that Florida has it's own set of issues.
I've always wondered, and maybe this is the place to ask, why not tunnel under the existing tracks (with a leading and following slope) and re-enforce the roof, that would no doubt be cheaper than lawsuits and elevating the whole line, no?
Brightline, in particular, runs on literally the first train tracks in Florida, set down by Henry Flagler. The urban economic development (ie: number of people) around those tracks in the last 100 years simply has to be seen to be believed. That's what makes it unsafe and also nearly impossible to change.
