I can’t talk much about serverless, I briefly tried some frameworks during the hype and I haven’t been convinced. It did sound more annoying and expensive than copying files using ftp to cgi-bin or mod_php managed servers like in the 90s and 2000s.
About software containers I think that the complexity is very very much worth it. Being able to ship software that run on my machine and will run about the same in production is so convenient. Running applications with conflicting dependencies is not a problem. Installing up to date or legacy software without breaking the operating system is also trivial.
Sure kubernetes is complex but it’s a bit more than running containers. A good start is using Docker or podman directly. You can see the value of kubernetes or nomad later.