You would have to feed in a half dozen+ legendary ayanads to even go from legendary to mythic. And youd have to also feed in delphs and Ephs legendary first of all to get the exp closest as you can to 99% without going over to maximize overflow into next grade. And before that youd have to feed in four epic ayanads, and before that 4 divine ayanads, and before that like probably close to 100k worth of fodder, and then to even make the erenor in the first place it's a LOT of expensive materials. It is a long process and everything after celestial erenor requires RNG with regrading, so you'll be breaking celestial/divine/epic weapons HOPING to be able to progress your erenor further if RNG is good to you. And this is WITH the exp nerf, so try to quantify that gold.
Meanwhile, in current patch mythic obs weapons have sold at t5/t6 for 300-400k and then upping to t7 is just farming those mats (even gets cheaper in 3.5!)
Now you tell me which is easier to get. There is a reason obsidian is discontinued on live.