Also for the "but Rails is more expensive to scale" people: Procore's IPO filing showed gross margin of _82 god-damned percent_. Shopify's gross margin on their subscription solutions (the Rails monolith) also hovers around 75%. Are you not entertained?!
Actually, I just checked Shopify's 2019 results and they're doing 80% now. Nice!
This all tracks with Basecamp's recent assertion that they're spending about 15% percent of their ops budget on Ruby: https://m.signalvnoise.com/only-15-of-the-basecamp-operations-budget-is-spent-on-ruby/