I am not sure, if I am missing something here, but I think those numbers are still pretty decent.
However, activation time can be significantly impacted by poor links between sites. Maybe the connection to the affected site is experiencing deteriorated network performance?
please note that its not only the hosts config that are pushed, also rules, notifications and even local scripts if you might have those. its done on every activation.
all this travels on your network so if you feel 40 seconds is a long time you might need to look into your WAN or whatever connects them together. I dont find 40 seconds a long time.