I expected a pretty biased and negative video by the title but I was pleasantly surprised by your remained objective outlook. Thank you
I believe Coinbase wouldn't risk any forms of insider trading but it's probably very hard to completely prevent with bitcoin transactions being partially anonymous.
As far as I'm concerned there were very low btc fees on Coinbase just now making it a perfect opportunity to get some more BTC with lower transfer fees plus a 'discounted' price.