Oh, I certainly don't have an anti argument. We'll end up destroying ourselves, be obliterated by cosmic events, or eventually run civilization from computer simulations.
People have just been saying "real soon now" for 60 years. Obviously we are more "real soon now" than back then, but it's still unclear how soon we can be.
My favorite knock down is the "when computers get fast enough, we'll magically have AGI/hard AI." If that were the case, we could have really really slow versions now.
Theoretical vs. practical architectures matter. Nobody can imagine an iPad's software ecosystem if your model is vacuum tubes and single tape turing machines. But when you hit CPUs, shrinking processes, and GPUs with 6 teraflops on a card, you see how impossible your goals were with a 0.2 MHz room-sized computer with 500k of memory.
If you immediately know the candle light is fire, then the meal was cooked a long time ago.