Furthermore, the compiler is very chatty about not inlining, so someone has been ignoring warnings.
I have editted the wiki warning to explain what really happens.
Please note that this "chatty" behaviour is only since 3.2.0 (or some time in 3.1.1).
Also your warning is not quite right either: it's not only about code complexity, but also about the compiler not supporting something. E.g. in 3.3.1 the compiler gained support for inlining functions from another unit that accesses local symbols, thus the "can not inline" hint disappears for such messages and thus user shouldn't remove the
inline directive as future versions might improve this (also it's simply a hint, not a warning...)