There are multiple layers to unpack when it comes to email delivery.
To answer your rhetorical question, yes mail does get lost even with email, particularly where the conditions are not right.
1. If you're using a private email host that isn't a free host like hotmail etc, check with them that they've not had any bouncebacks when you've sent emails to forums@guildwars2.com -- your mailhost should be able to read what's going on through information obtained in the headers on the bounceback if at all.
2. If you're using a free email host like hotmail or gmail, your inbox can still reject them without you knowing. Hotmail is notorious for this, and requires you to whitelist the potential sender by adding them as a contact to override the global mail filtering preferences set by Microsoft.
There are a number of possible reasons why you might not be "receiving" the reply, but these are the most common when it comes to receiving emails from ArenaNet/GW2.