Microsoft announced all games would be in the program. That is no longer the case. Now there are only 12 games to be in this program. And the PC copies aren't free; you still have to pay $60 for the Xbox One copy to actually get that free copy.
Wait...what! Did you expect to get the PC version 100% free...as in they will just give everybody a copy? It was always stated as a buy for this platform and get this platform version for free.
There aren't only 12 games to be in the program neither. There are only 12 games currently announced for the Play Anywhere program.
See, this is what I meant about Microsoft protecting themselves.
We have to remember that Microsoft publishes a lot of games from 3rd party developers, it would be unreasonable to expect all those parties to jump aboard this new initiative.