If you make an assumption of ever-increasing technological means, it will *definitely* happen. The only question is "how long before it does?".
It won't happen. You obviously have little knowledge on the scaling of large systems (distributed vs centralized vs decentralized). I'm not saying that we will never be able to process a lot of transactions; I'm saying that we will never be able to process more than a centralized and well expanded system like Visa (on chain transactions). I have no idea why some people think that we can. Their TPS is already a few thousand times higher than what Bitcoin is doing.