There are more factors to take in here then "havoc is bad literally right this second".
If you look at pre-nerf and post nerf 1 Havoc was parsing proportionally higher, which would suggest it simply doesn't scale well with corruptions as opposed to the spec being weak in of itself
Of the 10 tiers it has existed for it's only been in the bottom 50% twice, that's got to be a better strike rate than any other spec.
Even when it's performing poorly it has among the highest representation of any spec.