For businesses that sell things, yes, sales are a gigantic part of what matters to a company.   Look no further than Nintendo readying new hardware,  a tad over 3 years after the Wii U's launch, as proof that sales in fact, do matter.

They don't need to do it. I personally have never really cared about it. I buy the console for this gen, to play the games from this gen. MS kinda had to do it to help try and draw people to buy their console, and close the sales gap. Well, that didn't work.

Well, it would appear that the PS4 is the far more compelling piece of hardware this gen, from a consumer point of view, as voted for by wallets.

Never once have I booted up my ps3 since purchasing my ps4. I don't think I'm alone here...I think you are.

I rather have BC and the old backlog available than having companies bragging about new games when they are only a way to sell you the same games on new hardware.

It was a big deal to current xbox owners. You can't base everything on sales. Yes, this is a sales site. But this is also a place for forum discussion. Alot of Xbox owners (including me) were happy to see this feature. In fact I played through the whole of Mass Effect, and I loved it!

Anyway, just don't always say "sales matter". Enjoyment is a part of the experience as well, and pleasing your fans can give you good karma over time.

What non-anecdotal evidence do you have to suggest that PS4 owners aren't enjoying their experience, and aren't pleased?

You are however correct about good Karma, which is why Sony ended last gen extremely strongly, building goodwill that's quite clearly carried over into this generation. 

All Sony consoles had it before PS4, in fact Sony started it. BC was not even a thing till PS2 came along and they continued it with PS3 (which originally was BC but it lead the HW issues).

We never had it before, and all was fine. Really there is no reason why they couldn't just install an emulator via firmware update or in the store and let it go like that. The problem is wether or not the owner of the IPs for these older games will allow games sold for PS2 to be played on PS4. Sure Sony is to blame for some, but publishers want every penny they can get and if they can resell it at a cheaper price and minimal effort, thats what they are gonna do.

Now the only reason the X1 is doing it is because they need something to stand out, or I promise you they would follow suit. As you can see however, not all games will be BC on that either as some publishers will not allow it.