There are full-stack developer jobs, but those are often quite hard to fill for the exact reasons you outline: if someone has really mastered 5-10 frontend tools as well as 5-10 backend tools with 5-10 years of real-world work experience with each, then they aren't going to want to take a "normal" salary.

Full-stack jobs often pay less than other jobs, so they end up being more indicative of "we are desperate for programmers but can't afford to pay them" more than anything.