@yogthos I think a nonzero amount of this, is that talent dried up in the paid-for sector.

Solaris was huge in the early days of the web; but all the "cool kids" ran Linux at home. It got harder and harder to find sysadmins skilled with Solaris, whereas Linux experience was everywhere.

Because of this, the Linux admins were cheaper to hire.

Software licensing isn't the biggest IT budget item anymore, salary is.