The main flaw with 5e when it comes to advising GMs is the absence of knowledge that was gathered over decades of play and no mention of the design intent behind certain archetypes. New GMs are left to figure out that wizards have more explicit tools for interacting with just about everything and if generous allowances or accommodations are not made they will mechanically eclipse the fighter in a neutral setting. The game doesn’t suggest running a setup where the GM gives the fighter more opportunities to shine, nor does it tell prospective players that the fighter will be more dependent on the GM for such opportunities. We know what happens in each case, WotC knows what happens in each case. They designed the fighter to explicitly lack those levers but neglected to tell players what to expect and GMs how to provide opportunities to the fighter players that want them.