Exactly this. The outcome of these studies/articles is always: you don’t need it… if you eat healthy.
Now look at obesity rates etc, do you think most people eat healthy? Now would these people benefit from multivitamins?

If you’re hosting websites and not applications, perhaps you can use SSGs like Hugo/Gatsby. You could deploy your site in a bucket and put cloudflare in front. They can also be used on your own server of course. If you are hosting applications and want to keep them on 4g, you could put a CDN (CloudFlare or …) in frint of it. That would cache all static resources and greatly improve response times.

Portainer + caddy + watchtower, this will give you the benefits of containers without the complexity of Kubernetes. As someone who professionally works with Kubernetes, I agree with what other people have said here: “only run it if you want to learn it for professional use”.

Portainer is a friendly UI for running containers. It supports docker compose as well. It helps with observability and ops.
Caddy is an easy proxy with automatic Let’s Encrypt support.
Watchtower will update and restart your containers if there’s an update.
(Edit: formatting)

What nonsense, of course you can write safe code in other languages. What makes it safe is the people that are experienced in writing it securely and test it. But not all code has a high standard of quality, due to time pressure or due to lack of skill. So yes, the only way to be sure you have safe code without spending more time on training and testing is if the language does it by design. Has this guy ever worked in software engineering?

I would suggest using Caddy. I think it’s a little simpler than Traefik and can automatically handle LetsEncrypt SSL/TLS certificates for you

My 2c, buy RPi’s because what makes them so great is the availability of drivers and information. You will end up paying with your time if you try to save some money up front. I had several OPi, one randomly started throwing errors. After several reinstalls with various sd card, the information I could find was that the SoC itself was causing the errors. Also getting any hardware to work with it is just a major pain, driver support is severely lacking. Support for the Linux versions is community driven, so you’re dependent on Armbian maintainers. If you have a very new or an older board, you’re probably out of luck when you want to do anything outside of Linux. Example, I could not get a camera and BT module working. I later bought a RPi4 and had the same hardware working within hours.