Worse than, for example, offering microtransaction packages in Assassins Creed that cost so much money there is not even enough content to unlock with them? Unity does that. Hiding gameplay elements behind it? Black Ops 3 does that, Overwatch will not Blizzard announced.
No, and stop talking bullshit. Do you think anyone gave a fuck if "chop chop", "lets go in sneaky beaky like" and so on would be behind a paywall in CSGO? Also, the speechlines are randomized. Tracer can randomly say "cheers love, the cavalry is here" or you get the item and you can press a button and say it whenever you like.
Every character in Overwatch has way more lines than just one. So please, nobody imagine that. Because OP is bullshitting you. Yeah and sure, the game gets more immersive when i can spam "that is SIR for you!" with my Soldier 76. Mind you, i do spam it all the time, but only because i am one of those hateful online players who would shit on my own team in chat if i had no other option to vent. (sorry for that by the way guys).
So you CAN unlock those speeches? Nice. By the way, if you want speech, its fucking cheap. You can buy tons of it till level 20 if you want, i already got every line for every character i want. Only through ingame currency.
You know who hides actual weapons behind randomized drops? Call of Duty, with Advanced Warfare and Black Ops 3. You cannot get those weapons through missions, events or anything. Just luck. You cant even buy them through a micro transaction, just pure RNG luck. Is that maybe worse? (hint: it is!)
So OP calm your ass down. You are overreacting way too hard.