With BTC supply set to dry up very soon, many questions are beginning to pop up like:

1. what happens if every last BTC is bought?
2. how do we control liquidity after then?
3. are we gonna be vulnerable to price manipulation?

The answer is to bring utility to Bitcoin. The only way to achieve that might be "defi" - bringing true programmability to Bitcoin L1 and make the $4T liquidity readily accessible.
Babylon opened the possibility of defi on Bitcoin network by enabling native BTC staking using the interoperable cosmos sdk though not on Bitcoin L1 which leads to liquidity fragmentation.
Now Bitcoin devs have began building the possibilty of a true "defi" Bitcoin network and one of those earliest protocol is Portal to Bitcoin where native swaps between ETH, SOL and BTC is gonna be possible using PTB as network fee.
Being one of the early users of this protocol (using a native wallet) has got me believing that defi is indeed possible on Bitcoin L1.
Just maybe, the imminent launch of PTB (set to be listed across several T1 exchanges like BG soon) might just be the necessary drive towards achieving defi on Bitcoin.