DeFi is still more like a failed experiment, 80% of DeFi projects are unreliable, they have weak security and they are more hack friendly, they claim to be decentralized but instead they aren't showing any decentralized motives, the only DeFi projects I trust are not up to five and I choose those DeFi projects because they are more than just DeFi like many new DeFi projects so far, I don't care much about where DeFi is headed, I'm just going to keep picking the good eggs out from the bad eggs, hopeful in future DeFi projects will actually become fully decentralized and more secured
I don't think DEFI as an important sector of crypto space is a failure, there are many good projects where Investors have enjoyed huge returns in term of daily rewards and coin price appreciation. Pancakeswap, Apeswap and Bakeryswap are good examples. Having said that you are right that there are many scams and insecure projects which I am sure will die when they fail to deliver promised results. We need to be good in cherry picking when we invest our hard earned money in any project and should do good research work before taking investment decision.
Very important part of investing is to have a deeper investigation with our pick asset, there are a lot of project that we can look sorting all the potentials and segregating what are good from what are not, DEFI introduce potential but same with ICO back then they're also lots of scammers that use the same venue to scam investors money, without carefully doing your research you may find yourself being victim.
Treat things the right way, take time to do deeper research and never to be moved by trending projects. Most of the time, it leads investors to lose their money.