This is a cue that the updates themselves are screwing everything up. My Surface Laptop and Pro 3 both got real good battery life before any updates came across and went downhill from there.
I do believe that most updates (except security updates) are not needed and the problems that about 90% of the machines are 'user configuration' problems. A lot of people don't know how to set it up properly because there is no documentation on the operating
system itself. Thus, people are using the "old tricks" used all the way back to windows XP which will not work.
For firmware updates, you cannot roll back and remove them in most cases. Other updates you can by viewing the Update History on the Windows Update panel.
Microsoft is still working on the power issues and even if you could remove the old, new ones will take their place to probably make things worse.
As for 4 hour battery life for general use - you was supposed to get a few hours more than that. So, your machine was a 'storm drain' from the start. The Pro 3 gets about 6.5 hours (before updates). About the same 4 hours after the updates like yours.
The Surface laptop - I don't measure it since it is using Insider Builds for which come across every couple of days now. Nothing counts on it.