Because Sony make most of their money from the platform, they make barely anything from 1st party games... so the priority should be adding users and building a unique portfolio of games, similar to how PS4 had a strong generational portfolio that sold the console to even some of the strongest PC gamers.
PlayStation is a hardware platform first and foremost, it is even in the name 'Play' - 'Station'. Either they put the console first and expanding the base of users or else the whole thing will not work anymore.
If they didn't have a hardware platform, games like the ones they make simply wouldn't be viable.
Also in terms of investors, Sony's entire stock jumped based on hardware forecasts being optimistic.... not on software, no investor gives a toss about anything except how many consoles they get installed. They are not waiting on how many units GOW or Spider-man sold, they are waiting on how many million consoles they sold each quarter and how they can top the last gen.