It seems you yourself are a novice investor then, given your...

It seems you yourself are a novice investor then, given your posts following mine in this very thread.
No, it has nothing to do with any of the "severity" or "impact" of the "crime".
It has to do with something much more fundamental - that is the nature of the allegation.
1. ASX are a platform to trade SOI. The total SOI and MC of a company must be known, or reasonably estimated.
2. A large portion of the ISX SOI are under question by ASIC.
3. ASX must prevent the trading of 2), in order to preserve their function as 1).

It's as simple as that.

The rest is irrelevant.

When WBC have 30% (or even 10%) of their SOI being questioned for validity by ASIC, then you can ask "Why is ISX suspended and not WBC?"