Going forward, this is meant to be contructive feedback. Please keep that in mind.
TLDR section can be found at the bottom of this reply.
To be fair, granting only those who reach 3% completion regardless of World Quest failure is just the same as neglecting all of the efforts put into it for those who spent countless hours just getting to the 0,5% milestone or barely made it but in the end and was not rewarded because it failed. I had the same opinion as you after my first WQ, which also failed. But, I have since changed my opinion, because it felt selfish of me to be thinking that way.
I assume that this suggestion came to blossom after the failed Bidoof World Quest which seem to have failed on both servers alike. Let me tell you, making 3% on the Bidoof quest is significantly easier and less time consuming then getting it in any other normal tier 8 or tier 9 World Quests. Still, if you believe that they/you should be given a reward regardless, I'm not entirely against it or I wasn't in the past. But, I am against this suggestion if things like special World Quest events like the Bidoof World Quest isn't excluded from this reward. Why is that? Because effort should never be neglected and it is way too easy to get 3% on it, making it practically useless and unfair for the rest that also helped participate and got over the 0,5% milestone.
And I did say it is "way too easy", but this differs for everyone. I know that getting roughly 48 068 IVs (bare minimum IVs for Gold server) isn't a easy task for the Bidoof WQ. And I'm not neglecting your efforts when I say this, but you would have an even rougher and harder time in a normal tier 8 and tier 9 World Quests, which also seems to fail more often then not. Practically rendering this suggestion pointless, as it will only benefit people in most cases on special WQs and that I am heavily against for said reasons above and below.
Honestly, make it fair for everyone who participated and not neglect all the awesome people that helped bring it closer to 0.
I'm not saying that a individual should not be rewarded accordingly for their efforts, but never neglect the rest of the participants for your own selfish reasons. Doing such will not amount to anything and it pains me to see this.
Hmm, idk if this is meant to be a reassurance for this suggestion or you just straight up ranting about your loss.
So... Here, let me enlight you with a short story about my first World Quest on PRO.
It was around 1-2 years ago that I found myself intrigued with the World Quest and decided to finally try it out for the reward it yieled for the first time. However, this was unfortunately posted right before, what would later be known IMO as PRO's worst timing for a Special Outbreak.
Earlier that day, the World Quest was announced, it was irrc a tier 8 or 9 Pokemon. The worst nightmare for any hunter, people were mad in chat, everyone was on edge but they still continued to push forward. People were saying that the WQ might actually be successful despite the odds. However, little did the community know that a super Rare Outbreak with irrc Star Wars sprites with a high spawning chance was about to unfold. I was at that point already on my 11th hour online still hunting for a Skitty and was barely passing 1,6% mark. There were only a few hours left and irrc about 40,000+ IVs remaining. I was at 2,4% when it ended. But I still hunted for 4 hours straight, and there were only 1 other dedicated person hunting with me on that location for the entirely of the hours remaining, and I believe the other spot were also pretty much emptied right after the special Outbreak was announced. It was sad to see how my first ever WQ failed and on top of that, I were that close to my first ever 3% on a 100,000+ IVs World Quest ... I dedicated my entire day for an event that yielded me nothing in return, that had taken 15 hours of my life and amounted to nothing, because I kept on submitting the captured Pokemon after I hit 0,5% the first time because PC storage and to be sure that I lowered the number so others would submit too. Honestly, it was a real punch to the throat. So I understand the frustration of wasting hours for nothing, and furthermore going into 2022 with no rewards for your efforts.
For the record, Waleed1301 have already suggested this back in 2020 and or potentially others that I've missed on the way.
https://pokemonrevolution.net/forum/topic/146408-small-change-in-how-the-world-quest-works/
TLDR;
Make it fair for everyone who got 0,5% or more. Do not neglect the effort of everyone participating. Perhaps give rewards to everyone who participated in some way to compensate for the loss to at least yield something back for all the effort one have put fourth. Its easier to get 3% during a special World Quest then it is in normal World Quests (tier 8 and 9), which renders this suggestion pointless.