I had an external HDD that I was using for years. Some of that time it was attached to a Server basically running 24/7 definitely dropped that thing a couple of times. That HDD has been out of use for years now but I’m sure I could just plug it in tomorrow and it would spin up fine. HDDs can last forever untill they don’t.

So Backups! And don’t worry about the rest.

Also as others said if you’re interested how long and hard it’s actually been working check out the smart data if there are any fail criteria you might wanna get a new one just to avoid restoring from Backup but if all’s green just let it keep chugging until it doesn’t and remember Backups!

They absolutely do have “Startup Applications” in gnome not sure what the article is describing but I usually use gnome-tweak which offers a simple interface that shows currently running apps and a list of all apps and easily lets you select them to start at boot