There's not really not much more room for Microsoft's consumer software to grow, but the next quarterly report must show black numbers, so the only way to stay profitable is to produce software in a way that is cheaper than the previous month.
Incidentally, neither a rigorous quality control process, nor a team of experienced engineers is particularly cheap.
Growth mindset can be such a cancer. Many mature businesses don't need to grow and are perfectly fine as they are. You could continue running them forever, making steady cash. Or you could enshittify them, make slightly more money for 3 years, and get overtaken by competitors, all the while pissing everyone off and wasting billions of dollars.