Eh, we all know it is up to WWE creative and Vince to decide who gets gold or not. Often the reason is to help wrestlers get over with the crowd or lend legitimacy to a gimmick they are pushing (Reigns as a "bad-ass" for instance, or The New Day conglomerate). It is actually a good thing, to me, that Enzo and Big Cass never captured gold in their run as a tag team.
Jim Duggan was over quite well with the crowd. Never held gold.
Cryme Tyme were over extremely well. No gold.
Jimmy Snuka is well remembered and loved by many fans. Again, no gold.
Jake Roberts rocked an amazing gimmick that had fans cringing but no gold around his waste.
Junkyard Dog had a great likable gimmick and was over with fans really well, especially younger ones (much like Enzo is). There was never gold around Junkyard though.
There are many more I can point out that were really over with the crowd in one way or another yet they failed to capture gold in their careers. Being a champion is not the end all be all for a character - though I am sure it is a rush none the less for the person portraying that role.