I’m a 50+ non-geek Linux user myself, and selfhosting is the one computer ‘thing’ I would love to be able to setup one day but I’m too afraid to seriously start doing as I’m way too afraid of being that ‘low hanging fruit’ you mentioned in your post.

Dude, 70 here. Just do it. You’re going to make mistakes along the way, you’ll learn along the way. You’re already a Linux user, so you’ve got a leg up there. Even if you walk away from selfhosting thinking it’s probably better for you to use those small companies, you’ll have had an enriching experience. I find selfhosting to be rather rewarding in many aspects. For one, it’s one of my hobbies that keeps my mind busy which is a good thing. I’m always digging for something new to learn.

If you are the only user of your server, tying it down becomes a lot easier. allow.host / deny.host, tailscale, ufw, and fail2ban will get you very far and safe so you won’t be that low hanging fruit. I am quite certain there are people here would love to help you on your way. I’m one. I’m an expert at nothing, but I don’t mind sharing the knowledge (?) I’ve learned along the way.