Author is saying that early decisions made by an un-diverse Twitter staff led to the company's problems today (as it's having hard time growing [partly] because it has an abuse problem [I guess towards women]).

Does it not occur to him that having a more diverse team might have led to other bad decisions being made which would mean that company would have never even got off the ground?

His logic strikes me as someone looking at a floundering NBA team and saying 'Well, if you just replaced a few players with women, you might have had a much better chance of winning the playoffs'.

In other words - if more diverse teams led to better results, wouldn't there be a bunch of examples for this? As it stands, the best companies in SV are all terribly undiverse.