Victor Vasiliev wrote:
I suggest to use <a> for external links extended syntax and parametrized [[]] for internal links so we can easily distinguish them. --vvv
Kalan explained it "<a>s may be used by spammers, by the way."
A talk page gets added the text 'This page explains it <i>pretty well</i> <a href="http://example.com">some webpage</a>'
Currently, you see the html garbage, realise at first sight that it's a spambot and revert. If <a> were an accepted syntax, you would doubt if it's spam or a person trying to use wikisyntax.
It's sad not being able to use the logical tag, but I oppose making valid the spammers messages.