The ROI of learning web development has never been higher. With modern-day frameworks and tools like Firebase anyone with knowledge of javascript can build apps. Exciting times.
It is a mess, but that's usually because those easy to use frameworks make them a mess. Big site inevitably are going to be filled with a lot of JS that for things you're not going to implement anyhow. Start small, build upon previous knowledge, incrementally.
Something like Stackoverflow easy to build these days? What about marketplaces?
I’m still intimidated by webpages when I “Inspect” them with browser tools.
CSS especially looks a mess to me and it puts me off from learning web development.