These are huge and will eat up a really large amount of memory!
Uncompressed size:
misrock atlases - 4096 * 4096 = 67 108 864 bytes
main atlases = 8192 * 8192 = 268 435 456 bytes
rubber atlases = 4096*4096 = 67 108 864 bytes
Total size: ~400MB
It’s not even certain that all devices support 8k textures. Check these stats: https://webglstats.com/webgl/parameter/MAX_TEXTURE_SIZE
Are you really using all of the graphics at once? Is the graphics perhaps larger than it needs to be (ie are you scaling down the game objects to get the proper size on sprites etc)? Are you using texture compression (more details here)?