> There's a huge gap in how easy it is to upgrade some stacks vs. others.
This I can agree with.
> Updating dependencies in a language with strong, static types and/or an expressive type system is incredibly easy
Java would typically be regarded a pretty close to .NET in regards to its type system, yet I've seen plenty of issues with updating dependencies, whenever you have any sort of dynamic class loading or reflection going on: be it Lombok or MapStruct not liking a specific version of Java, or Spring Boot or one of its many integrations throwing errors during startup after a successful compile, sometimes even disliking specific annotations that worked previously.
A decent type system will help you make sure that the code compiles, sure (and I'm thankful for that), but with some styles of writing code and handling, for example, dependency injection, all bets are off. The same goes for any dependencies that make liberal use of those features. I'd have to dig around for specific examples, but I know for a fact that there are plenty of projects that are stuck on old versions of Spring for that very reason.
Or the fact that there are plenty of pre-.NET Core projects out there that won't be upgraded to anything new anytime soon for similar reasons.
In my experience, updates suck across the board, the only variable is how much. And that applies to everything not just dependencies in code (and runtimes): I've also had seemingly innocuous Debian updates break GRUB and prevent the OS from booting, or even upgrades making exim4 start up for some reason and taking up the port that my mail server needed, preventing it from starting.
