Systems that fail to ensure that such emails cannot be automatically
generated (by adding CAPTCHAs for example) need to be updated.
This is not possible. CAPTCHA is not a silver bullet. What it can do for sure is preventing simple automated actions on the orders of millions, maybe, but orders of hundreds of thousands are still achievable for a skilled criminal.
I know some are lucky to have it working for now, but there's no guarantee. Therefore cannot be a requirement.
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