_low_type_ is early days still, but I think this approach is clearly the future of ruby typing. If this gets baked into the language for full “compile” time support and minimal performance impact, it will be amazing: https://github.com/low-rb/low_type
It is definitely better than RBS and Sorbet. But unless Github / 37Signals or Shopify decide to use it, it is highly unlikely Ruby Core will consider it.
Out of all three I think Shopify have the highest possibilities. There may be additional usefulness interms of ZJIT.
Previously, RBS-inline was the closest answer to typed Ruby, it was the JSDoc of Ruby. Recently, when I stumbled upon low_type and tried it out in irb, it finally felt like ”this is it, this is the TS of Ruby” and with runtime validation.
I like it, it deserves attention, especially for those who are seeking for typed Ruby. With this, you can finally experience it, and the syntax feels more ergonomic than with Sorbet.