I really don't understand this view. Where is the so-called "charade"?... no need to continue the Bottas charade.
Mercedes has two goals in F1, to win the constructors championship, and to win the drivers championship, in that order. The very best way of doing that when you have a dominant car is to have one stand-out driver to take the drivers championship, and a very decent "second" driver to bring consistent points and ensure the constructors. That is exactly how the Hamilton/Bottas setup is working.
The very worst way to do it is having two stand-out drivers fighting amongst themselves, hampering each others races, and potentially taking each other out on a regular basis. This is exactly what has happened when teams have had two ace drivers in the past. It's surely very good for us to watch, but spectator entertainment is of secondary importance to the teams after performance.
So having Bottas at Mercedes is not a "charade" at all, it is a very sensible and calculated decision to ensure Mercedes' continuing success and dominance of F1. Boring yes, charade no.
As for Russell, I don't think he'll get a look at Mercedes until Hamilton confirms he might be leaving. Why potentially ruin a good thing by bringing a young and hungry driver into the mix? Toto already alludes to allowing Hamilton whatever he wants and needs to stay on top of his game, and I'm sure that includes team dynamics whether either party admits it or not.
But as others have mentioned, we all know that speed and talent has little to do with being in F1 these days. It may be the "pinnacle" of technology, but it certainly doesn't have the pinnacle of racing driver talent. There are at least three drivers we could name right now who have no business being there at all, and should be binned in favour of fresh talent. Perhaps the incoming cost caps will start to help with that as teams become less reliant of pay-drivers, who knows? But as it is now, good drivers are always going to be losing out to mediocre ones until skill becomes the priority.