I definitely use this same style of GMing, though I don't know that I've ever prescribed it a name beyond the vague mantra of "create problems, not solutions".
Like your system, I populate my world with various Actors that are just out there doing stuff, causing problems, making chaos. My current Campaign the players took the bait with the first problem I dropped in front of them, but in the background there are several other world events that I had plotted out as being viable options.
Now that we're already going down one rabbit-hole, I've folded in one of the other plots to become an active sub-plot to the campaign, but if they decided to just up and ignore this current threat to focus on something else... I could easily pivot because there is still at least one other Major Problem that's out there, and it wouldn't hurt the world at all for them to just abandon their current mission.
If anything, it'd let me have the bad guys win and in like 12 more sessions after abandoning this line, they'd have a brand new problem to deal with. 🤣
RE: GM Tips: Using "Fronts" to Create a Dynamic World