Could be. But in this strange and bizarre world of crypto, people often link a cryptocurrency's market cap to its success. Which means that if ETH gets "flipped" by Tether USDT, all the attention will be on the stablecoin itself. It's good to know that the ERC-20 token version of USDT has the most transaction activity, as it benefits the underlying Blockchain (ETH) itself. Since ETH is used as "gas" for USDT transfers, it could benefit from USDT's popularity in the mainstream world. A good thing USDT has relative to other stablecoins on the market, is that it "lives" on multiple blockchain networks. In case a Blockchain network fails or becomes disrupted in the short term, USDT can still be used via other chains. People can use USDT with lower fees and faster transaction confirmation times, by switching to more scalable blockchain networks such as TRON or EOS.

I believe that USDT has gone all the way to the moon in terms of market cap, because of the hype surrounding "De-Fi" and Stablecoins in these times of turmoil. We'll have to wait after the demise of COVID-19 and the recovery of the mainstream economy, to determine whenever USDT will maintain such position on the market or not. For what I know, a stablecoin overcoming a traditional cryptocurrency like Bitcoin or Ethereum won't make any difference. That's because a stablecoin is entirely different from cryptocurrencies we know and love today. It's like comparing apples vs oranges if you ask me. All in all, it seems that centralized stablecoins will have a very bright future. Just my thoughts