That dungeon gives you 3/20ths of 1 scale. It isn't on the daily every day, and I know I can't do it solo. So maybe every other day, so about 540/20 = 27 full scales / year. 27 isn't enough to level up 1 item. Even if you did it every day, that would be 365*3/20 = 54 full scales over 1 year. Each accessory takes at least 7 fragments at level 3, 6 and 9, 10,11,12,13 (11-13=awakened). So 1 item takes 49 scales. There are 5 items.
Other dungeons give those items as well, but none of them are soloable. H0, SP and the newest one in the heavenly realm. In addition to 5 accessories, your weapon requires them, as well as your heart, soul pet and token. That's 10 items that require ALOT of those scales and only 3-4 dungeons you can get them from -- all at the top of difficulty.
So claiming they are easily available is bogus -- sorry but you ain't my pal unless you want to start carrying me everyday to all of those dungeons. And how often do I hear whales whine about taking HM<18 along? Thanks for your note, you just forced me to prove the issue. Only when you are past all the ET items and accessories and are into the steel series do you stop needed them. Percentage wise, not many of the players are done upgrading items that need those scales. If you think the scales are plentiful, it means you are collecting the steel-even items. Congrats, maybe I'll see some of those in several more months. Right now a full equipment purchase of those is over $20,000. Not everyone can afford such equipment.