Not going to engage with ridiculousness. If you are equating pulling a curtain down on someone’s head and flying to the moon, you’re not looking to understand but ridicule.By this logic a commoner is also just as capable as a spellcaster, since you're only metric appears to be "can they replicate some version of overlapping impact of a spell with enough time and effort." With enough time and effort, real nonmagical people have put men on the moon..all it takes is a few short centuries of aggregated scientific progress.
What it really boils down to is there are 78 pages (just in the phb alone) of specific narrative shortcuts, designed and incorporated in the existing action resolution mechanics requiring zero additional DM bandwidth for a player to select and use.
Also, thank you for again clarifying that you believe it is the martial player's lack of creativity and nonspecific DM intransigence that is the root cause for this feeling of imbalance here.. not that for one set of PCs, the designers have specified options for what a player may do and how they should expect for that action to be adjudicated and for the other set, the designers have said "yeah, you can grapple..and you can shove...and..et cetera I guess..your DM can figure it out".
Because here's the thing, by your metric for the bar that the designers needed to clear to provide adequate mechanical support, the entire spell section is unnecessary, you could just have the caster's players roll a contested check, have them describe a spell, and let the DM make it work.
Spells have always been very specifically described. When you are altering the laws of physics it helps to be very precise. That’s why spells only do precisely what they say they do. It’s also the reason why there the 76 pages that you get so hung up. You don’t have to read them you know.
There are about a dozen actions a fighter can take in combat. The designers sensibly didn’t try to do what pathfinder did and game out every single possible action because they have GMs. Then they expressly encouraged GMs to use skill contests to adjudicate these.