Depends on what he means by web developer, also why he thinks cybersecurity safe from the same threat.
Automation is already a large part of the industry, but that’s very different from AI replacing the job, much less than the entire field. Web development really is larger than just building websites. My company is in the midst of migrating to a cloud-native architecture, and while individual pieces are simple and faster to write and deploy, the complexity in the design and orchestration of a reactive, resilient system still very much needs a human touch.
No offense to your father or other software architects, but because of their job is to look at the higher level design and evangelize certain technologies and practices, they are sometimes separated from the reality of people doing the day to day implementations. They often have an ideal version of how things should be, but they don’t quite account for or underestimate the tedium and all minute outliers the coders have to go through day to day. That’s been my experience.
The requirement collection process can be so tedious and obscure that even humans struggle to understand and fulfill. The same goes with debug support that developers provide when the code does go wrong or requirement changes and communications with other teams that go on during implementations. It’s not going to be as simple as feed in the requirements on one end and code spits out the other side. That may be doable for something stands alone, but in much more complex systems and it is maybe not quite as simple.