How to make gold nowadays?
Farm flax from the new maps. Farm coarse sand from Silver Waste. Sell dungeon runs. Sell shovels to guild willing to buy them. Do meta events on the new maps or old dungeons for rare skins to sell or mats to sell. Many materials needed for guild upgrades are sellable if you know what you’re doing and if those guilds are willing to pay for it. Do event trains on maps that give good rewards. Level your mastery and sell your services to people if you wish.
IMO chest farming is not the way to go. You get plenty of sand just doing events.