USDT is designed to track a steady value, while TON, TRX, and ETH move with the broader market — sometimes up, sometimes down, on any given day. For a Telegram Stars purchase, that distinction matters less than it might seem: the checkout locks in the rate the moment payment is confirmed, so whichever asset is used, the amount charged doesn't shift mid-transaction.
A card charges a fixed fiat amount by definition; paying with USDT keeps that fixed-feeling experience since its price barely moves, while TON, TRX, or ETH bring in market pricing that a card wouldn't have — the locked checkout rate keeps the actual charge the same regardless.
Whether the asset used is the stablecoin USDT or one of the market-priced options — TON, TRX, or ETH — the checkout process and the rate-lock at payment time work identically.
No — once the checkout locks the rate, that's the amount charged, regardless of what the market does afterward.
No — this is only about paying for Telegram Stars, not investment guidance on which asset to hold generally.