Earlier quoted context omitted.
The whole point of the internet stack is to abstract away the details of the lower layers. A web developer does not need to know TCP. They need to know HTTP. Even if they did know stuff about lower level networking the browser completely locks you out of that level.
The abstractions are super leaky. Infrastructure fundamentals are consequently significant in all applications. Failure or refusal to understand and inwardly digest this leads inexorably to bad software, or more precisely, bad systems. Web developers that do not know TCP/IP and do not wish to are a consequent burden to everyone else; a fountain of horrors arises, from latency issues to security blunders, when mechani…
I still disagree. As a web dev, there is absolutely nothing you can do to affect the networking stack. This is all completely buried in web servers and the like. Most CDNs are complete SaaS tools where you can't anything beyond the highest-level. Everything devs do to optimize performance is at the application layer. You can observe things like latency or number of connections and change your code or infra, but you're absolutely never going to inspect a packet. Unless you're actually developing those web servers.