This worked out not only because Microsoft had the money but, critically, because they had the will to make Xbox a success. They resolved to slog through the years of losses, failures (anyone remember the Japan launch?), and missteps in order to build a successful business.
Whilst Google have the money, more than enough money, to do the same, I don't think they have the will.
From my own perspective, as a gaming enthusiast, Stadia simply isn't solving any problem that I have, and I don't believe it's going to be around long enough that I want to invest in it.
[1] I'm sure they would have preferred if it wasn't.