All good points, I've seen some sites with every plugin years out of date when I've helped friends with theirs, weak passwords, that sort of thing.

I've always done my own hosting too, just a minimal setup of nginx, php-fpm, and mariadb on a 1GB RAM VPS. That way I can keep the server side up to date with security patches, instead of relying on a webhost that may not do it.

Backups run nightly offsite, and I monitor the sites with Change Detection so if a plugin update does break something or in the worst case a site gets hacked, I know fairly soon and can either fix it or roll back to a backup.