Engine Yard's management took several strategic missteps over the years. One of them was stifling Merb. The quotes from Yehuda describe his difficulty in making the best of a forced merger.
Ezra's vision for Merb and DHH's vision for Rails were distinct. Both warranted development. Over time, I assume they would have collectively strengthened the Ruby community. It was a mistake for Engine Yard's management to have instead framed it as zero sum and forced a merger.
I wrote a book on Merb and was an active contributor. Before that I had developed several apps with Rails.
That said, the Rails vs Merb era was mostly good natured competition and I don't view the Rails vs Merb period as itself having been problematic.
Merb devs believed we could make app development both simple to start (as a single file like Sinatra) and easy to evolve (into a modular codebase with Rails-like conventions). Existing outside of the Rails ecosystem allowed Merb to pursue that distinct vision.
The Merge between Rails and Merb, accreted many of Merb's modular architectural enhancements to Rails, but sadly deprecated the overall Merb vision. To me that was a shame, but I still wouldn't describe any of it as toxic.
Ezra's vision for Merb and DHH's vision for Rails were distinct. Both warranted development. Over time, I assume they would have collectively strengthened the Ruby community. It was a mistake for Engine Yard's management to have instead framed it as zero sum and forced a merger.