... Yeah, as 73ms already pointed out... that first link is just someone setting up an AppView.
To truly run an independent BlueSky system... you would have to run your own PDS, your own Relay, and your own AppView.
Your second link does actually have code and a rough setup guide to running your own Relay, so I will give you thanks and credit for showing that at least it is possible to theoretically do this...
But you say 'several people run their own Relays' and then do not evidence that.
The Relay config here is just... how to host your own Relay that would act as a member of BlueSky's Relay network.
Basically, that is just how to transfer some of BlueSky's server hosting costs ... to yourself.
If you set up a totally independent Relay... could it even interface with BlueSky's Relays?
As far as I can tell: No.
It would be totally independent... a parellel network, not a federated one that interfaces with the rest of BlueSky, and is thus not actually able to 'federate'.
What... you would have to do... is set up your own Relay, connect it to basically all the other preexisting PDSs you want to include, then also run your own PDS, then also run your own AppView, and connect it to your own Relay... or just trust someother person running their own AppView, or just trust the official ones.
(But... I think that to connect your own Relay to preexisting PDSs... that would require those PDSs to... disconnect from the mainline BlueSky Relay system... because they can only point to one Relay system at a time... so that's kind of a problem.)
That would be the only way to make your own ... sort of branch of the BlueSky system, that at least in theory might be resistant to centralized censorship from BlueSky.
And again... I am not aware of anyone who has yet done this, or if it would even work at a technical level.
When dealing with software and tech companies, a good rule of thumb is that a planned or possible feature... doesn't actually exist untill its been provably demonstrated to exist and work.
... I get the jokes, but I really, truly was just trying to use a real world example case to illustrate a functional aspect of the system, and not just ... you know, bring up all the drama.