That's just expectation, not certainty. Everything can happen in this halving... time will tell it, we only can speculate what it will be.
I didn't get what you said, how can you buy ETH, XRP, or USDT will get BTC? You are like saying you buy a pizza, but you want to get a cup of coffee. Please tell more specific
I guess he means about when some altcoins were getting an increase in the bitcoin pair and he was taking it as an opportunity to get more bitcoin. Some altcoins over-performed bitcoin. That's the main point that he wanna try to say with us but that's only some altcoins and it's also too risky to consider the dump can occur anytime.