Do not believe them. Everything they did was intentional. The way rewards are obfuscated via an additional currency (experience) that hinders your ability to gauge how much your time is worth in regards to rewards, the way they intentionally tied achievement exp to legendaries you don't own yet, the way they assigned weekly quests to playing legendaries of an expansion that isn't even out and you might not own now, or ever.
They knew this would cause backlash, they planned to make this statement, they will increase rewards but it will be in no way greater than what we had before. Hearthstone will remain the most expensive F2P card game in the world, with massive barriers to entry and increasingly stingy progression.
They know no one will be able to figure out that they have been truly shafted until 4 months from now when the next expansion rolls out and people have less gold to spend. They will say anything to fool you until that point, but only the cold hard truth of your own situation will convince you.
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