Yep, and this is why "inside IR35 contracts" should not exist. They are basically zero-hours temporary employment contracts, except with the "employer" dodging their responsibilities.
However, there is an interesting point when it comes to this: If there is no Mutuality of Obligation, is there any employment? Is a zero-hours temporary contract employment? There is no obligation for the "employee" to accept work, and no obligation for the "employer" to provide it...