I expect a Camry to keep on working with regular, normal maintenance.

I'm probably doing something wrong, but in my experience the amount of magic that Ruby allows (and RoR and library creators use), create for situations where updating code is extremely risky. It can be mitigated by having an extensive testing-codebase, but those only tell you if your assumptions still hold up, they don't help you in fixing your issues per-se.

And half of these tests are checking that your invariants are being upheld, things that you get for free with statically typed languages.