I could believe that wire nuts for regular size wires (say, 12 awg) have a pretty good reliability record -- only after they've been twisted together by an experienced electrician and then capped, there is great wire contact and physical strength. I've occasionally had a wire slip from a Wago when I do a test pull.

But I'm with you, I'm happy with Wago. When I'm doing the work myself, that's what I use. Though I do use wire nuts for my big wire connections (6 awg). They probably don't even have lever nuts for that size, but I didn't look.