Magic Find Bugged?
Even with magic find, drops are still random. Magic find increases the chances of something dropping, but it’s still up to chance. It’s totally possible to go through a stretch of time with improved magic find and still get nothing because each monster you kill has an independent probability of dropping something nice. Just because you had this happen to you once, does not mean the entire magic find mechanic is bugged.
There is plenty of data that MF has a powerful impact on your drops, but it’s not the only factor.
Take the extreme example of Player A decked out in maximum magic find equipment and Player B using maximum DPS. In this unrealistic scenario, imagine that Player B’s build allows her to one-shot AOE all the baby spiders that pop-up in the area while Player A is only able to get credit for killing the toughest foes. Player B will get 5-10x more drops than Player in the same time period, including more opportunities for blues, greens, etc.
When deciding whether to go full MF, partial MF, or no-MF, you also have to consider how efficient your build is at tagging and killing foes and how effective you are in comparison to other players.
Finally, as Apocolyte discusses above, the law of averages doesn’t cover small bursts of activity. Player A (above) could get very lucky in any given run and get substantially more loot than a very unlucky Player B. However, every controlled experiment I’ve seen involving Magic Find shows that you get more of just above every type of loot (junk, mats, whites, blues, etc).
I could be bugged. Look at my post: https://forum-en.gw2archive.eu/forum/support/bugs/Monster-loot-as-lvl-80-vs-non-lvl-80-bugged/first#post607389