How bad is battery life on Linux laptop?

I will need to get a laptop in the foreseeable future, and I really want to stick to Linux. However, I may need to be out-of-home for 12+ hours straight in a day. After some research, it seems people are generally not that impressed with battery life on Linux?

The laptop does not need to do anything heavy duty, as I will remote back into my already very beefy desktop back home.

I guess a common solution to this light use case is M2 MacBook if one wants to completely throw battery concern out of the window. Well... let's just say it's a love-hate relationship.