I have never transacted in Tether in any kind of way except being on the exchanges.. although I think that when I had a Bitfinex account between about 2016 and 2017, I had Tether on that account, but I don't know what form of Tether, because when they forced all USA users off of their platform, I am pretty sure that I just converted all of that to BTC to transfer my BTC off of that account.
From about 2018 to 2021, I had a Binance account that used Tether (but I don't recall which type), and when they forced me to stop using their service in 2021, and per their recommendation, I decided to move all of my then Binance balances over to a new account that I created on their BinanceUS branch, and I am pretty sure that I transferred the Tether, but I had not remembered whether that was on Ethereum, even though it appears that the Tether that I currently hold on BinanceUS is ethereum based.. that seems to be the default. But if I go to withdraw Tether it gives me the below six options
Note: Avax C-Chain, BNB Smart Chain (BEP20), Ethereum (ERC20), Polygon (unavailable), Solana and Tron (TRC20). There is not even a Bitcoin option of apparently Omni or Liquid.
By the way, I recall that BinanceUS made me switch from Tether to dollars in 2021 (or maybe I did it on my own), and then earlier this year, they discontinued dollars, so I chose to switch to Tether, and I have been using Tether on BinanceUS ever since, even though I had not realized it was the Ethereum based on. .or maybe it does not really matter which one of the bases it is since they are holding it.. but if I am going to transfer it, then I have options to use either the ethereum or the tron version if I were going to move it over to Aqua... since neither Liquid nor Omni seems to be available with BinanceUS... which is all news to me.. if I am not repeating myself a bit too much on this point. hahahaha
https://help.blockstream.com/hc/en-us/articles/900005355626-How-do-I-get-Liquid-based-Tether-USDt-
Fortunately, it seems that there are more exchanges supporting Liquid BTC https://help.blockstream.com/hc/en-us/articles/900000629383-Which-platforms-support-the-Liquid-Network-