Someone asked me why it's been 10+ years but DeFi still doesn't exist on Bitcoin. Here's my answer:

The bar is very low when it comes to pursuading USD or altcoin holders into parting with their coins. They are comparing DeFi oppourtunities to altcoins and USD.

When Bitcoin is your base unit, you compare every other oppourtunity to Bitcoin, and DeFi has thus far offered absolutely nothing even remotely worth the risk.

There's no technical reason you can't do at least some aspects of DeFi on Bitcoin, but a DeFi product targeting Bitcoin will have its economics, technology, and security model compared to Bitcoin by some of the sharpest minds on the planet.

There's no scope for well dressed ponzi schemes, trusted third parties, or winding back the blockchain like Ethererum etc when someone makes a mistake.

DeFi has been possible for about 10 years now, so where are all the 10 year old projects with a proven track record?

I don't even think there's been a DeFi project that has survived more 2-3 years before the underlying economics cause it to collapse in on itself. I haven't seen anything that would survive under a Bitcoin standard.

That said, it's absolutely coming, and arguably already here on top of lightning. But I don't see any existing DeFi players with the competence to engage this market.