Tweaking the ini is not outdated but it’s just not as mandatory as before. Unless you really are pushing the boundaries of photorealism you don’t need to mess with that. Especially not when starting out with the engine. There are ton of more important features to learn before tweaking the baselightmass or other .ini
Ini files are just a way to access settings that are not present within the editor’s interface. Usually all you need is already accessible within the interface. Some people just want a little bit more control on some parameters.