I don't think we did learn anything about modularization in the past 20 years. Programming languages still don't do it even remotely decently. Users still make a common mistake of splitting things into multiple files for the sake of splitting, just as your comment implies. These things are all about UX, which is known to be neglected in programming.

This is merely an example server with a router, middleware and two route handlers. This isn’t evangelism for monolithic application design, and there’s nothing inherent in Go that forces monolithic application design.

Having to rebuild thousands of binaries every time a vulnerability is found in a popular library is seriously hurting Linux distributions.

That, and having to handle vendorized dependencies.

> Having to rebuild thousands of binaries every time a vulnerability is found in a popular library is seriously hurting Linux distributions.

Do you have a source for this?

"Putting everything in one binary" is what we learned in the past 20 years. Most major languages either compile to a single artifact or they have some "bundling" trick to minimize runtime dependencies. Besides that, there are things like Docker which exist to solve the same problem.