That was my experience as well (seeing many brilliant engineers leaving after deciding they've had enough of being let down by MS). Lack of other people on my team that I felt I could look up to and that I enjoyed working with was a big factor in why I left. I suspect the brain drain from MS will only accelerate over time though there are still a lot of truly excellent engineers working there.
Though I only worked at MS for a few years I suspect that the current working environment, culture, bureaucracy etc. problems have been building up for a very long time but were offset by remaining enthusiasm (read: kool aid aftereffects) and the enormous financial incentives from stock options. Now that the MSFT stock price has been flat for nearly a decade and it's increasingly easy to find tech jobs with comparable salaries a lot of the luster of working at MS has evaporated.
Though I only worked at MS for a few years I suspect that the current working environment, culture, bureaucracy etc. problems have been building up for a very long time but were offset by remaining enthusiasm (read: kool aid aftereffects) and the enormous financial incentives from stock options. Now that the MSFT stock price has been flat for nearly a decade and it's increasingly easy to find tech jobs with comparable salaries a lot of the luster of working at MS has evaporated.