I do both embedded development (day job) and web development (night jobs(s)) and it's not that embedded tasks are simpler, it's that you don't have to deal with

I do both embedded development (day job) and web development (night jobs(s)) and it's not that embedded tasks are simpler, it's that you don't have to deal with a ridiculous stack of third-party code that is constantly changing. With an embedded system you know and control every component of the system, right down to the CPU bugs, and as a result your application code is much, much simpler. You can reason about and understand everything; there are no black boxes. The safety thing is not a big problem in practice. Your companies have lawyers, regulatory teams, risk assessors, standards and code reviews. You will thoroughly test everything to ridiculous detail (in my experience, 30:1 ratio of test:production code). Mistakes happen, but by the time they manifest in reality so many people will have had a hand in it that you won't feel personally responsible.