you have an indirect way you answered yourself. People value and invest in Bitcoin because it is a decentralized currency and it is also an asset so having bitcoin as asset is what makes people to value it and be interested to it. I believe that cryptocurrency he said kind of currency that I appreciate people's funds but not like Tether. Tether is stagnant currency which does not add any value when who did why Bitcoin add values and also reduce values thats why some people do not value it.
Yeah, people do not invest into tether because tether is ruled by a company and not decentralized is the number one thing, plus they are much shadier than their competition as well, I would do to BUSD and not USDT if I was investing into a stablecoin as well, so decentralization and trust is one of the reasons.
Secondly, I do not invest into any stablecoins. Because, it is clear to me that we are talking about a situation where it is going to be just the same price at all times, why would I do something like that? I mean crypto would go up and make me some money, if I were to invest into stablecoins, I could just put all my money into regular dollar as well. But crypto means better returns.