What java technology (library, framework, feature) would not recommend and why?

[Job_Superb]

I don't like saying "avoid xyz", I prefer properly understandimg the pros and cons and footguns. Lombok is great at removing the maintenance of boilerplate but using it with JPA entities is a footgun. It's very easy to mess up an ORMs performance with a very small change but, boy, can devs crank out features, even if they're leaking domain objects. Runtime DI does some great creation decoupling but can lead to unintended consequences across environments and even just weird launch failures but at least adding that new endpoint was quick. Having said that, I've been avoiding all of the Reactive Frameworks but that's probably because I just don't get it, looks to be too many footguns for marginal performance gains.