I understand your position. There is a learning curve to containers, but I can assure you that getting your basics on the topic will open a whole new world of possibilities and also make everything much easier for yourself. The vast majority of people run containers which make the services less brittle because they have their own tailored environment and don't depend on the host libraries and packages and also brings increased security because the services can't easily escape their boundaries rendering their potential vulnerabilities less of an issue compared to running those same services bare metal.

I started on synology too. There is a website called Marius hosting which focuses on tutorials for containers on synology, but his instructions have been updated the last few years to focus on spinning up containers manually rather than through the UI, which makes it more intimidating than it needs to be for beginners... I'll link it here just as a reference. I'll see if on the way back machine he shows the easier way and report back if I find something.

Edit: yes here is an original tutorial for Jellyfin (this method still works for me and is still how I use docker lately): https://web.archive.org/web/20210305002024/https://mariushosting.com/how-to-install-jellyfin-on-your-synology-nas/