>Is Rails still that good?
It is but;
Coming from Go, you will likely find Ruby and Rails to be relatively slow. Depending your definition of performance that could be acceptable or a no go. However Your development speed may likely be 5 to 10x.
The good thing is that Ruby is not I/O Bound is finally gaining momentum. After years or decades of I/O Bound we have finally come to may be it really is more CPU bound than we admit it to be. And things are improving. YJIT improves real world performance by 20-40%. If you measure only the CPU part and not total response time that is 30-60% or in some cases even more. There are still more optimisation could be done.
Rails and ActiveRecord are also improving. Shopify, a $150B market cap company now has all the incentives to improve Rails. YJIT is work from Shopify.
And throw more hardware at it now makes sense more so than ever. CPU Cost / Core is falling faster than ever. Thanks to competition from AMD EPYC and AWS Graviton / ARM. 2026 we will have 256 Core Zen 6c. We may have 288 Core Darkmount this year. You could quite literally have a single monster server that is enough to serve unless your site is Top 5%.
Database is less of an issue, starting small you could use SQLite which is now well supported by Rails 8.0 and it is enough for most. Planning big just use PlanetScale which uses Rails internally and is being used by other Rails site including Github.
The whole ecosystem is basically ready for you to just work on business logics.
I am hoping we get more defaults, Rails finally get authentication with 8.0. but could do more work. We will hopefully see more improvements coming in Rails 8.1, and so much more to come from Ruby side as well.