Because it is the most widely spoken language in the world,
And is relatively easy to learn and it is easy to transport a lot of info clearly and quickly in English. So yes, it would be good.
However, if the driver was not sober, or just lost, English might not have saved the day.
The reaction in Russia right now seems to make a neutral accident investigation/report less likely than I would like it to be.
But maybe the MAK and others will surprise us all.