Interesting Video. You get the impression that all are very good in fast autofocus, very close to DSLR, and differences between cameras are minute. In this discussion here it sounded that difference between cameras and between mirrorless and dslr are much bigger. But perhaps birds in flight are more difficult than motobikes in flight :-O
Most definitely the thing is we all love our gear choice,a lot of the arguments being put forward against mirrorless i was using 12 months ago.
I don't think you will fail which ever way you go.