They will sell all these games on their console and lock people into their ecosystem and then they will sell another 2 million copies on PC as a bonus.That is your view.
By putting their games on PC, and seeing people buying their games, it would make them focus more on putting their games on PC.
If you are a business person, your main objective is to maximize your profits. Holding your assets for too long, would not generate them money.
MS makes double money from PC and Xbox, due to day1 price.
Because old games go on sales fast. Day1 games go on sales late. So you maximize your profit in those first 6 months.
Just selling 4m copies on steam, is enough to recoup production cost. They get $180m at $45, after 30% cut. That covers the cost of the game. Whatever they sell on their platform would be pure profit.
What can't you understand here?
These games literally beat back several times on consoles, and bring Sony long-term revenue.