On a more general note in huge texture size, and the fact it can provoke crash, we have no control on Chrome crashes itself, it's more of a browser issue.
On sketchfab side, We cannot get the VRAM from the video card as browser vendors considers that a security breach (buffer overflow and user tracing using hardware info as fingerprints)
That's why we encourage "reasonable" usage of textures, which is what can fits on most hardware.
The math for the "reasonable" usage is: texture of 4096x4096 is around 100 Meg of Video RAM. (jpeg or png is not a supported format in the Video Card hardware aka GPU, so it's uncompressed 4096x4096, with 4 channel, * 1.33 for mipmaps (better texture filtering on distance).
So 20 4k textures is at least 2 gb which exceeds most user video cards.
That why Artists uses all possible tricks to lower texture needs:
- transforming wide range of uniform color or normal no texture (vertex color instead) or very small ones
- Text texture are the one needing the more quality and and could be separate textures
- trade texture space against vertex complexity (use vertex deformation instead of normal maps for relatively big details, vertex color instead of texture color, etc)
- ask on forum for other tricks
Imho, it's the best and most likely to work solution.
If you absolutely need this level of texture, you can try with appropriate hardware and hope for the best...
So a video Card with Huge VRAM (4go would be a min) with the hope that chrome or any browser doesn't limit RAM/VRAM artificially, would be a way to check if it's possible to render that many textures, but we cannot make no guarantee there.
Please note that huge texture size not only makes crashes, it also makes for very slow rendering on GPU, so you might get a very very slow model rendering anyway.