The GPU and SSD are actually the only thing that are really egregious here for the price. That 570x should be a 2070 or 5700XT, however... it's still a custom build case, PSU and the mainboard isn't off the shelf stuff either, so it's always hard to judge the price properly.
That proprietary stuff comes at a price (on top of it being more expensive), though... you won't be able to replace Mainboard and PSU, so that makes upgrading the CPU in around 4 years (or sooner) impossible. In the unlikely event that either fails (and you're out of warranty), you're SOL... you have to buy from DELL.
You can't just replace the mainboard from a DELL PC, you'd have to buy a new case and PSU since off the shelf MoBos won't fit and the PSU most likely uses proprietary connectors, which means you can't simply replace the PSU either (it's usually the 24-pin ATX connector that is different)... replacing the PSU is most likely impossible anyways, since the case here has also a custom place for the PSU.
You can't simply throw the internals into a new case either, because frontpanel connectors most likely won't fit... so you end up buying almost everything new, except for RAM and GPU. You can make everything fit in another case, but you'd have to frankenstein something together to make it work.
This makes it actually a lot harder to upgrade in the future... except for GPU, RAM and SSD... I mean, depending on Next-Gen consoles that i7 9700 could last for 6, 7 or 8 years for 60fps gaming, but who knows.
If I were your friend, I'd buy a pre-built from someone who uses off the shelf parts... the best one would be a shop that lets you pick the parts and THEY built the PC for you if you really don't want to build one for yourself. I think iBuyPower.com lets you do something like this, here in Germany we have Alternate.de for example.