You don't need to lock speech to make money. Blizzard will be making money of skins and other stuff to finance continued development of the game. Stop making it an all or nothing situation. Blizzard could have 'spared' speech from the unlocking treadmill.
And like i said, i know how paradoxical i sound. Gameplay unlocks are garbage but you could see it coming or how some devs would chose it. Who the heck saw speech unlocks coming? Who thought these characterization and 'personalitization' voice lines as something too add to the unlocking process. Blizzard went there. They went somewhere no one thought existed.
You know what? They could've. They also could've arbitrarily spared any number of systems away from the unlock treadmill. They ALSO could've abritrarily added yet more systems into the unlock treadmill.
I do not think it's a radical idea that they would lock certain taunting voice quips behind the treadmill because at the end of the day they need everything they can to subsidize the future development of this game. While I think we can all assume Blizzard is going to make their money back on this, at the same time we have to think about how this all started. Is Overwatch not sort of the remnants of the failed Project Titan? How many years and money was thrown away on all this during that time? And then they come out and still say "Oh by the way all future maps/characters will be free for people who bought the game". They needed every little thing that they could nickle and dime to make the risk assessement of this work, while still not crossing the line into "Direct gameplay affecting unlocks". And very likely, even something as dumb as voice taunts got stuck in there too.
That's all it is. I personally would love to live in a world where MTAs didn't exist. But I don't think we can reasonably expect a company the size and scope of Blizzard to function on just the game sale alone anymore. Especially if they plan on continuing to develop/support the game. MTAs are a necessary evil to keep the bloated triple A machine alive. Making them affect as many non gameplay affecting things we can is the best case scenario we can get.
Either that, or be willing to accept an overall increase in the upfront cost of a video game from this point on.
If anything this should be more of a criticism of how AAA games need to function to survive. The kind of money they need to bring in just to be successful/break even. Development costs go wildly up, but the upfront cost of games isn't changing enough to compensate. MTAs are the compromise.