There is not a single most important factor here everyone is going to agree on and drive a clear decision.

While I've argued in the past we should use Composer and "barrier to entry" should not preclude that, that does not mean barrier to entry is irrelevant even in that arguement. It just means Composer is a wildly used and easy enough to use tool that we should adopt it.

While JS is still challenging for me and my gut says the answer here should be Preact or Vue, React (or even Angular) doesn't have such a high barrier to entry that it should be dismissed on the topic reason alone.

Everyone here has a different rubric and needs to accept that what is important to them individually isn't the same as what is be the for the project long term. I'm still unclear what is best for the project long term or that anyone can agree on the rubric.

The best surge think I've seen is actual prototypes of dashboard modules and how to extend them with any of the proposed frameworks. WP's most key feature has always been it's extensibility and the reliability that those extensions would continue to work through years of updates. Maybe a contest is in order to do some small thing both ways, see what shakes out.

I will say the the I think Calypso/Automattic's familiarity with React should _not_ weigh heavily here. I get the temptation for that but WP's choice should always stand on thier own.

Other than that, looking forward to whatever color the bikeshed ends up.