Because they went back to a badge-upgrade system in the form of flightstones. The war/titanforge system was always about making you grind shit over and over again until the item (hopefully) dropped with one or the other. That's without the random secondary stats (if the item had secondary stats). I too, also wonder why anyone but oblivious casual players disliked that system lol.
Not that Blizzard couldn't just bring back reforging all secondary stats with 100% conversion and solve part of that issue. Although knowing Blizzard they'd just bring the D3/4 enchanting style of reforging to encourage wasted time. But yeah, RNG on top of RNG drops with a good chunk having RNG secondary stats... lol.