Unsurprising that it "caused user confusion" since unlike with imessage, SMS messages were not synced with the hangouts desktop client so chunks of a merged conversation when viewed on the phone would be missing when viewed from the desktop. If conversations are to be merged, they need to look the same everywhere. The half-assed implementation that hangouts used is worse than not merging them at all.

As someone who uses Google Voice, my SMS messages are synced with the desktop client. This is a significant loss of functionality for me.

This feature was valuable with iMessage before Apple added that synchronization, and frankly I bet in the grand scheme of things the vast majority of people using these features on both iOS and Android do not ever try to use a desktop to manage these messages (and in the case of Android probably don't even know that's possible, as at least with iOS if you have a recent version of Mac OS X you are highly likely to discover the feature by accident).

I wonder about that, given that Hangouts is directly embedded in GMail. There might be quite a few more people who use Hangouts on the desktop.

They're free to disagree; ostensibly they may have telemetry on it. But it was a feature the user could opt into if they so chose (if I recall, it was in fact opt-in [1]) and now they no longer have that choice.

[1] http://www.greenbot.com/article/2971862/android-apps/how-to-...

Well, yes, obviously it was a feature that existed and could theoretically be used -- that's not in dispute anywhere; there's a pretty big gap between that and being a feature that was, in practice, actually useful.