Why has fixed-rate borrowing stayed so thin?

Variable rates are still the default for most onchain credit. That makes leverage and yield farming messy: you can size a position, then the borrow rate or farm APY moves against you before the thesis plays out.Fixed-rate markets exist in TradFi because treasurers and lenders need duration. Onchain, that layer has been thinner for years. Curious what people here think is the actual bottleneck:

• Liquidity fragmentation (borrowers and lenders won’t sit in a fixed pool)
• Smart-contract / oracle risk making duration unattractive
• Better returns still living in variable money markets and points farms
• UX (term matching, early exit, collateral management)
• Something else

If you do use leverage or farm on Ethereum today, do you hedge rate risk at all, or just keep terms short and eat the variability?