Guardian traps are a weird thing. They are incredibly gimmicky, and yet extremely strong (when not used like a traditional trap).
IMO (as some one who has played DH 'competitively' for a long time) any one who places traps and just waits for people to stumble into them/be pulled into them, is just relying on the gimmick side of the traps. However, when used in conjunction with teleports and pulls (not just tether) it can be really potent and requires a significant amount more skill. Admittedly, it is still very much a case of burst or bust, but bear in mind, DH has the tools to be able to kite and avoid lots of damage.
I've shamelessly plugged one of my videos to demonstrate, and yes, this is the "highlight" reel, but it's generally how most of my fights play out.
Please note: this is before the balance patch, and with the longbow and retaliation changes, this build has honestly gotten better.
TLDR: most people just play a boring 'stand in trap = get wrecked' gimmick (which isn't actually that good), BUT it doesn't have to be that way.