The sound logical reason for no chest is that CDPR wanted you to make choices and sometimes hard ones. Do you keep what you have or sell it. Do you take that new loot or ignore it. Only LIMITS can accomplish this. And it fits in perfectly with what a witcher is. You don't see Lambert or Letho or Vesimer lugging around multiple armor sets.
Yeah... if they had this goal in mind, when they designed the inventory system, then they failed miserably... and I don't think there is any feature in there suggesting that they were aiming for a system, where it matters what you pick up and leave behind.
Initially there is a lot of inventory space (even more now with weightless crafting materials), you can loot almost all of White Orchard with your default carry weight, so they certainly do not teach you too make "hard decisions regarding loot" early on.
And since 90% of the loot is generic vendor trash anyway, the only "hard choice" regarding loot, is "which items sells for more gold/weight unit".
There isn't even any real penalty if you pick up too much... you can still keep looting, even if overburdened, it has no impact on combat (like no longer being able to dodge). It's only side effect -the reduction in movement speed - is usually a non-issue, since Roach, or a fast travel spot are not far away most of the time to quickly sell all the trash you picked up.
However there is some vendor trash that the player still might want to keep... like trophies (more than 1 of each effect that is) or the few main quest weapons, no longer useful quest items, books/letters you already read etc.
There is absolutely no reason to keep this stuff except for "sentimental" value... and that's what a storage is for.
If they wanted a system where loot actually matters, it should look completely different than what we have now. I fail to see the harm in this unobtrusive feature...