It won't be increased with 2.3, but it will with 2.4 in 3 months or so. Older dungeons are getting awfully silly, I agree, but it's the system they decided to use so there you have it. They opted for extremely straight forward, boring itemization that doesn't really allow for horizontal progression of any substance so the only place to go is up!

This might change and evolve in the future, but they'll need multiple worthwhile stats for theorycrafters to bicker over like double/triple attack, haste (being different from skill/spellspeed), critical hit damage, skill augmenting stats, unique additional effects, etc. Obviously the way it's set up now, more main stat = better, especially since the ilvl gaps are usually wide enough that the only secondary stat to consider (when upgrading) is accuracy, and even then only to a point.