Some points I thought of:
- Physics would be totally simplified. No more broad/narrowphase, bounding volumes, etc... just good old per-vertex n^2 collision checks (well you would probably still want to use bounding volumes for stuff like characters, but you don't have to anymore!)
- Pretty much any form of preprocessing could be gone. BSP-Trees, static light/shadow maps, you name it. This could heavily simplify code, especially on the tool side of things. Moved an object, need to notify the build pipeline and rebuild the static shadowmaps? Nope, not anymore, just take everything as it is and use it
- Any form of manual optimization would be gone. Memory layout, SSE, Multithreading (for the most part), Assembler... I can't speak for everyone but I for sure would prefer not having to write Struct-of-Array style code, for the most parts.
- Oh, and lets not forget about all the GPU-centered algorithms. GPU-Particles, GPU-Clothing, GPU-Watersimulation. Would be way easier if we could just write all those algorithms on one processor, I personally find regular CPU-code easier to work with than ie. compute-shader based equivalents.
all object types could have all possible member variables for all object types (unlimited ram), so you only need one type of "uber" game object type for everything.
Uh, why would you want to do that now? The reason we don't have "uber"/god classes is not because RAM doesn't support it, but because its harder to read through on 100k line cpp file, than it is through 1000 100 line ones (since you are only interested in part of the code anyways). I mean, be it composition/inheritance or whatever, but a door is a door, and not an "if(i_am_a_door) doDoorStuff();" alongside another thousands of those in a huge god class, for every possible game object, unless I misinterpreted your intention here.