Years ago, Zalman used to make something like this that you could put a 2.5" SATA disk in [1].
It was much cheaper, but you needed to add storage. I wish they still made them. I normally have spare disks around and it worked out much more cost effective.
> What kind of firmware updates do you need to do on it, when its only purpose is to act as a screen?
On some screens, signal processing has been significantly improved in later firmware versions. New features are also not uncommon, such as VRR and HFR being added after release[1]. This is particularity nice for modern consoles.
It was much cheaper, but you needed to add storage. I wish they still made them. I normally have spare disks around and it worked out much more cost effective.
[1] -https://www.zalman.com/EN/Product/ProductDetail.do?productSe...