My understanding (perhaps wrong) is that the linux _kernel_ is in the host machine that is running the docker containers, and is not contained in the container image you define in the docker file & build into an image with docker.

So if you don't like how the kernel is configured, that'd require you to reconfigure the kernel on each host that will run your containers, independently of what is inside the container. But perhaps your question is about what is in the container, and not really about the kernel?

Maybe to make your question clearer: what are explicit examples of things that don't you like about the current configuration that you are trying to change or disable?

In terms of removing unnecessary stuff from a container image, the easiest/simplest way to do this probably depends on what application you're packaging into a container & how it is implemented.

For example, it is possible to build container image for a go application that starts with an empty "scratch" container base image (ie there's no layer of distro such as debian, debian-slim or Alpine Linux).

Not sure if this is a great guide but it has an example: https://medium.com/@chemidy/create-the-smallest-and-secured-...

The same approach of starting without a distro as the base layer of the docker container image won't be as easy for deploying a different application that does not contain its own dependencies and assumes it can load a bunch of shared libraries that the distribution provides & read files the distribution has prepared for it.