Hi. I know you meant no harm with your post and neither do I with my answer. I just want to explain some things about textures in Daz that you seem to get wrong.
Daz can work with any texture resolution (the standard now is 4k, that is, 4096 by 4096, but this is not a sound parameter -- I'll come back to it later), what sets its limits is your machine, in case of Iray, more precisely, your Nvidia card VRAM (because Iray is Nvidia proprietary and only works with their video cards). Also, of course, you need RAM to load the scene and its assets in your machine, but when it comes to rendering, you want VRAM because CPU rendering is a drag for Iray. Since the best Nvidia card is 24 GB, it's the limit of your scenes (you can add many cards and it will speed up your renders, but the limit is set by the card with the highest memory, that is, if you have a 24GB card, a 16 GB, and an 8 GB, if your scene is 8 GB, it will render using the three cards; if it's 16 GB, it will render using only the two top cards; if it's above, it will only use the 24gb card).
But being 4k (or higher) is not usually a sound standard because, in fact, the resolution will depend on the details you need, the size of the object, and the distance from the camera. For instance, if you render a character in normal size, full shot (whole body), and a giant showing only below the knee, even if both have 4k textures the normal-sized guy will have better quality because he's smaller (in fact, even if all Daz characters, with a few exceptions, come with 4k textures, the face has more quality because it's smaller than the torso -- and, before anyone tries to correct me, the 8k textures advertised for G9 was just for details of the new -- crap and just a publicity stunt -- "PBR" shader -- between quotes because the older shader was already PBR since Iray is PBR-based render engine).
About every Daz game using the same textures, indeed, unless the dev wants to customize it or create their own, if a game uses the same asset that is an object in the scene (that is, not a pose, a script, a light, a morph, etc.), since they come with their own textures, they'll use the same textures. This is not an excuse, though, because, just using BaDIK as an example, since there are many scenes wherein the background doesn't have a low-resolution texture, it proves that you can have better textures in Daz.
Moreover, for many backgrounds -- like walls, furniture, etc.) you can use seamless textures (that is, textures that the left and right border blend as the top and bottom) and, in the geometry part of the shader, multiply the tiling in order to increase its resolution, that is, if you have a wall let's say of 20² meters, you apply the texture (for instance, of 2048²) and if you multiply it (tile) by 40, you'll have an 81920² texture resolution; and when you can't do it in Daz because the texture must fit in the asset UV, you can go to a photo editor like Photoshop or Gimp and do it there.
