Want something fast and simple? Use Go.
Want something really fast and powerful? Use Rust.
Want something ubiquitous, with lots of developers in the labor market? Use Java.
Excuse my ignorance, but what is Ruby's strength?
Also you can short circuit a lot of what you said with Crystal lang (for speed) or Ruby on Jets (for ease of deployment, serverless, etc). At Arist (YC S20), we were able to fully rebuild our app in Ruby on Jets, pass a pen test, get SOC 2 compliance, all in under 12 months. This frankly would have taken years if we couldn't lean on the Rails ecosystem, and our Appdex score is 0.999 typically, and we are prepared to 10-20x our current traffic because everything is serverless and each endpoint in each controller automatically becomes its own lambda upon deployment. Yet we can lean on the usual rails app structure, and use gems and features designed for rails.
With things like Go, basic string operations like reverse string are left to the user to implement. In the ruby/rails ecosystem we have Active Support. To that same point, you also get the most fully featured ORM in the world in the form of ActiveRecord. No other ORM comes even close to the features AR provides.
To your point though, we do use Rust for image and gif processing in one small lambda. I love Rust, but there simply isn't a web framework with the "sane defaults, everything included by default" mentality of rails yet. Cookie management, CSRF protection, etc., are largely left to the programmer to configure correctly, and it's simply a waste of time if you are trying to iterate quickly as a startup.
Where you can really get into trouble is if you take rails things for granted, and then go to a framework in another language. For example, you could have been brought up on rails and just take for granted that cookies are encrypted by default, and not realize that your supposedly server side cookie secrets stuff in express is being set in plain text.
What I like about rails, though, is it tries really hard to stop you from doing something stupid. Strong Params is a great example of that. You have to really fight ActionController to get it to do something actually unsafe. By that same token, properly configured rubocop will catch 100% of potential SQL injection vulnerabilities.
So Ruby's catchphrase is "developer happiness". There you go.