I have done some basic research on this topic, but didn't came with valid conclusion as resources were not from well known or reputed sources.
Hypothesis: (Especially for residential users), people don't use local Mail programs (as Outlook).
Hypothesis2: When an e-mail link occurs, people will rather copy e-mail and paste it in Browser E-mail message than use Mailto option.
Hypothesis3: Mailto option will by default open Email software that is not configured, and cause user frustration.
Conclusion: Mailto option should not be set as default on E-mail links, and should be provided with redesigned replacement.
Any thoughts or ideas on this topic?