I recently sold some older parts with an i5-8600k and a Raedon Sapphire 2000-something for $300. I really had no idea what it was worth, but someone bought it at that price. I guess you're getting more power for less money.
For Elite: Dangerous that should be fine. And it's a decent price
But CPU, RAM, and Motherboard would likely need upgrades before you could get to modern games like Helldivers. To be fair that CPU/Mobo/RAM released in 2009. GPU is a mid-range from 2019 so it should be okay for mid/low graphics in 1080p.
Nothing beyond that GTX 1650 is going to have any value, that i7 870 is a dog, you’re going to be burning 95w for 4 cores, and you’re going to have problems playing modern games (for example Helldivers 2 is going to complain about AVX support) and it’s going to be hit or miss whether the motherboard in that system is going to support UEFI boot