It seems like SpringValidatorAdapter doesn't handle <list element> literal. It is sometimes expected, as far as I understand JSR 380 spec correctly. Please, review http://beanvalidation.org/2.0/spec/2.0.0.cr3/#valueextractordefinition-builtinvalueextractors and correct me if I'm wrong. Note <iterable element>, <map key> and <map value> too.
I hope that "Reference URL" contains SSCCE. Will keep it for some time. I've attached all interesting files just in case something goes wrong.
As you (will be able to) see, validator.validate(bean, errors) ends up with IllegalStateException. I would expect one field error instead.
One more thing: I believe it's not about "bean property versus direct field access". Getters and setters are here. To be sure, I checked not only BeanPropertyBindingResult but DirectFieldBindingResult too. Same result.