A key part of the economy is the ability to enforce contracts and give/receive loans. I'm a strong believer that of all the cryptos, Bitcoin is the only real money. Everything else services the role of a security or utility token. 

That said, I think DeFi on Bitcoin, so long as its not directly on the Bitcoin block chain clogging up the system and running up transaction fees, is the right move. 

This will allow economies to allocate wealth efficiently with real money.