I don't think applicants think you're serious, or a potential advantage to have on their CV.
If you were a really desirable opportunity, you'd be expecting applicants to pay you for the chance to do your dishes.
This has been the standard for over 10 years now.
Maybe update your ad to include how much you think applicants should pay for the privilege of a chance to impress you?
https://www.smh.com.au/national/nsw/young-jobless-pay-for-internships-20140810-102e6o.html