It's pretty clear that this is probably the reason ETH is falling more than most of the other top coins. EOS did have a year long ICO though and raised a ton of ETH, so its no surprise that they'd eventually dump it. The Bitfinex-EOS-Tether relationship is shady as hell though.
See I don't think so not only ETH entire crypto currency market is in big volatile. EOS will take time to reach like ETH, of course, we are seeing potential in EOS and generating high volume because people are getting more awareness about the EOS project.