I've been using Fedora since the old Fedora Core days. My current desktop machine was purchased in 2016 and I installed Fedora 24 on it. KDE is my desktop of choice. Since then I've upgraded with dnf system-upgrade. I watch the fedora users mailing list to make sure there are no big gotchas. But really, for a while now, the upgrades have been uneventful. The folks preparing the upgrades are doing a tremendous job.
Besides being my everyday desktop, I run an apache webserver for my genealogy research, use fetchmail to gather email from several gmail accounts and my ISPs email account then use dovecot as my IMAP server and serve that out to thunderbird on my desktop and K9Mail on my phone and chromebook. I use samba to share out some file systems to my Windows machine (it has Quicken to track my family finances) plus I back the windows system to one of those shares (plus some external USB drives). Then on the Fedora system I use rsync to an external drive to back up everything plus I use borgbackup to back it up to a second external drive. Even with all this, the upgrades just work.