I have 8GB, which I've had since 2012. Never had a problem - I run a lean Nixos with just xmonad and dmenu, chrome, emacs, and about a dozen open pdfs and video tutorials.
Since I have a desktop I do use rustdesk way more often to just boot into that.
But you’re doing much better than me.
You need to make sure you look at the model and the emc number and check that they match the battery you're buying. (Same for SSD upgrades).