I personally love Keychain and find it really easy to use, both as a user and as a developer.

I moved away from steemit.com to steempeak.com because they are using it.
It's now so easy to switch from one account to another or to perform transactions where my active key is required.
That's why I decided to implement it on SteemReply.
The only drawback of Keychain is that it is an add-on which cannot be installed on mobile browsers 😢

We are on a blockchain were "keys" concept should be understood by users, even newbies/normies.
On top of "login in" on the various fron-ends/apps, there is money involved.
I audited SteemLogin code and website and I am totally scared of what I saw (I will post about it) and I won't like the way Hive account@irelandscape tend to minimize the role of the posting key. Read all the comments on this post, they are very informative.

You are right, we need something easy and universal for users to authenticate, but not at the expense of security.
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