As mentioned backblaze is a good resource as they extensively look into this very question. What I’ve noticed in practice is that all hard drives are pretty reliable these days. If they fail they usually fail early in the first 6 months. Regardless of what you go with always have a back up.
When connected through wireguard can you access anything on the local network?
Also sometimes if you’re on an LAN trying to vpn into itself you get weird network issues. Does this issue also happen when you’re on another network and vpning back?
Also there’s a lot of great videos on YouTube to set this up things like Lawrence systems and network Chuck.
Not exactly sure what the issue is here but gave you the up vote for visability and hopefully someone smarter then me will know.