re: developed by Steemit Inc.
I've always understood it as the other way around. Regardless, there are people who aren't happy that anyone has their private keys stored, so whether that's a valid concern, or a great risk, the perception is there. Also, I know I've had trouble getting through steemconnect to log on to a site when the site was otherwise up and running. So, something was bogging down in steemconnect, and I know I've read that it's been down. So, whatever Steemit Inc's level involvement, they've opted for the separate wallet.