I think that's the point. Max did things in the stupidest way that could possibly work, and it did work, and was simpler than the "smart" way, so was he less of a "real" programmer than Mel?
I think for a kid, Max's code was great but ultimately you do need to learn to think about things like error handling, especially if your code is intended to go into "production" (i.e., someone besides yourself will use/host it).
No they are not, which makes the case for breaking up applications whenever possible. Some thinks that means micro services, but that's not my point.
The example with the image sharing is pretty good, because it only needs to share images. In, shall we say more commercial settings, it would grow to handle meta data, scaling, comments, video sharing, account management and everything in between. When that happens Max's approach breaks down.
If you keep your systems as "image sharing", "comments" and "blog" and just string them together via convention or simply hard coding links, you can keep the simple solutions. This is at the cost if integration, but for many use that's perfectly fine.