Oh, I absolutely agree with the parts telling people not to trust apps that promises free votes etc. But he goes way beyond that to assert that no decent apps will ask for the user's private posting key, or store them. This is just flat out false, as there can be many good reasons to do this. Or at least offer it as an alternative.
The posting key is something you should be able to use more frequently. Else, we may as well not have it at all.
You're confusing developers like yourself who spent months on months on just their mvps vs developers who are throwing sites together with no care for user security. The former are rare, the later are 99% of them. The risk to typical users who don't want to wake up to their account compromised is tremendous. Even good dapps get hacked. Tasteem, Dlike, Faircrew exchange, Utopian back when just to name a few off the top of my head. It happens. 3 clicks is on Steem Connect is a small inconvenience which is already taken by those same users for other dapps.
For me, Steem Keychain support is a MUST. If not that then at least SteemConnect. Otherwise, "No Thanks".