Resurrecting an old desktop—is it worth upgrading?

After having a Stream Deck and then installing Linux on an old laptop for my wife, I decided to try and resurrect an old desktop I built in 2016. Wondering if it worth upgrading the graphics card, or is the whole thing too old to be of much use.

Edit to add: No Man's Sky is my most played game. And I was looking at an 8gb Radeon card as an update, if that upgrade would make the system usable, then I will do that. Otherwise I will save for a Steam Machine.

Edit 2: I knew I had a better graphics card, when I got home from work I found it. It is a ASUS GeForce GTX 970 4GB GDDR5 PCI Express 3.0 SLI Support Graphics Card STRIX-GTX970-DC2OC-4GD5(https://www.newegg.com/asus-strix-gtx970-dc2oc-4gd5-geforce-gtx-970-4gb-graphics-card-double-fans/p/N82E16814121899?item=N82E16814121899)