Initially in Feb he was all about vaccines [1], then in a revealing interview on the Ellen show in mid April he mentions them in passing [2], next in late April he suggests a role for them in easing the lockdown [3], and finally in June (in a somewhat revisionist interview) he castigates the american public for not wanting to wear them [4]
[1] https://www.gatesnotes.com/Health/How-to-respond-to-COVID-19
[2] https://www.youtube.com/watch?v=5oEcxMfwJnw
[3] https://edition.cnn.com/2020/04/26/business/bill-gates-coron...
[4] https://www.fastcompany.com/90520896/how-do-we-beat-coronavi...
Contrast this with a number of medical experts in Asia whose simple advice back in January basically nailed it, including the need for mask wearing, eg:
https://www.youtube.com/watch?v=dcbJdRb6mds
It's a cautionary tale that even the richest philanthropists with the best advisers can fall considerably short, and may not even be aware of it...