Are you playing on or using an emulator like Dolphin ?
Searching for "wii rom highly compressed" online often leads to websites promising "100MB Wii ROMs."
Moderate. It is largely obsolete now, superseded by WBFS and RVZ. How to Compress Wii ROMs Yourself
The Ultimate Guide to Highly Compressed Wii ROMs: Save Space Without Losing Gameplay
The primary benefit of compression is reclaiming storage space. Highly compressed formats discard dummy data, meaning games only occupy the space required by their actual assets. Faster File Transfers
Downloading pre-compressed files from random internet sites exposes your device to malware and viruses. The safest, most efficient route is to download standard files or dump your own retail discs, then compress them using verified, open-source tools. Method A: Compressing to RVZ using Dolphin Emulator
Every standard Wii ISO file is exactly 4.37 GB.
A standard Nintendo Wii disc has a physical capacity of approximately (Single Layer) or (Dual Layer, like Super Smash Bros. Brawl