Won't deny it D&D might come with it's own set of limitations but I think that's the entire idea. For each class to face the exact same situation differently depending on their ressources + their second class eventually. It's an old system but it works so I would rather say there's a space for everything in this world.
From meta-gaming perspective I ( personally) prefer class systems cause otherwise you end up with a couple " best skills" you will be actually using + you can get the answer to potentially everything as a backup on anyone ( I'm specifically thinking about DOS:2 cause I think that's the most "classless" game I played).
Meanwhile the class system from this same perspective will make you grab as many represantatives of the " best class" as you can while still having other classes to cover the shortcomings. They will eventually end up having to deal with some situation themselves in a " non meta way".
I mean that from pure combat perspective cause it's true from roleplay side( and that's what you're hinting at in your post) it's actually extremely strange lol.
