People like Theo De Raadt might have had a fairly huge impact on killing BSD.

He might have alienated a lot of people from even considering bsd.

The Linux community also had a lot of help by vendors such as Suse and Redhat who had no problems implementing good ideas which were a bit toxic, but were available in windows. Commercial venders can make a massive difference (as well as government deployments).

The big problem has been people resistant to change