I'm already paying for everything that incurs costs: it's my hardware, streaming my media, on my local network.
The only things left are users & developers donating time and energy to the project - and right now there are enough of us doing that to keep it alive.
This is absolutely not something that needs a subscription cost.
If you want to help - https://jellyfin.org/contribute/
Having a server you can stream from - you're right.
For the other features, you're likely wrong. As in - the open source space hasn't come up with a viable solution. I use Plex for DVR, and beyond the one time fee it works. For DVR you need to get the OTA channel guide, and all the reliable services out there charge a subscription fee - which over time will cost more than the Plex one time fee.
Also, how good is Jellyfin at skipping credits and ads?
As I pointed out in another comment - I'll happily use Jellyfin once it is there. As of now, every time I try it the experience is worse than Plex. So Plex it will be till JF gets there.
Or - and I know people don't love this answer - just host it publicly. Yes - it requires some monitoring and a little bit of attention, but at the end of the day it's not that hard, and the risks are fairly low (even if it gets compromised - the world is not over).
Jellyfin has apps (which do incur a bit of overhead for maintainers in actual dollars) but honestly, as long as you're not on iphone, you can just build them locally and sideload them. No store/publisher required.
I primarily use the android tv client on a nvidia shield running a custom ROM.