Yes, Decentralized Finance (DeFi) has been very lucrative Basically its great because everything is client side so all you have to is make frontend websites for people to interact with, and even that isn't really necessary. You just need people, with wallets, to be able to interact with your smart contract easily. The smart contract you deploy has to address a pain point for existing users, typically by consolidating…
And with crypto prices going up we are probably going to see the next DeFi bubble.
If you want to build a DeFi app, You need to learn DeFi development and I have a course just on that: https://eattheblocks-pro.teachable.com/p/defi-development-ma...
I also have a youtube channel for blockchain dev: https://m.youtube.com/channel/UCZM8XQjNOyG2ElPpEUtNasA