I believe that the ESO patcher has a tendency to randomly corrupt game files somehow during the patching process. This would explain why many people report increased crashing frequency after patches, and also why some people crash and some don't on nearly identical hardware and/or network connections.
In my case, deleting ESO completely then reinstalling it fresh completely solved my crashing problem, which again points to corrupted game files.
Here it's crashing about every 30 minutes/1 hour (average) since update 6. Most of the time it's just random crashes, even when I do nothing and look at the friendslist or whatever.
Before update 6, not even once a week!
Really, I can't take this anymore.
Since the last patch I haven't crashed at all (still get a second of lag here and there, but nothing major). Before that, however, I crashed at least once a day. So I'm happy
"Feet are for walking. Hands are for hitting. Or shaking. Or waving. Sometimes for clapping."
- M'aiq the Liar