Wikipedia defines foreign language anxiety as follows:
Foreign language anxiety, or xenoglossophobia, is the feeling of unease, worry, nervousness and apprehension experienced in learning or using a second or foreign language. The feelings may stem from any second language context whether it is associated with the productive skills of speaking and writing or the receptive skills of reading and listening.
In the Western world (and probably also elsewhere), Chinese is considered a very difficult language, mostly due to its writing system. However, is the Chinese writing system also the most important cause of foreign language anxiety among (Western) language learners? If not, what is the most important cause according to the scientific literature?
(Note: native speakers of Japanese are excluded from the scope of this question.)