You're conflating 2 issues.
Yes. The actual assault weapons ban excludes bolt action rifles. It also allows detachable, unfixed, pre-ban magazines on semi automatic rifles.
Then you add a whole new element. The only time fixed magazines come into the conversation is if you're working on the false presumption that Healey's edict is law. Okay, fine. I'll play hypothetical, but it's all or nothing. You either falseley believe it's law - or you realize it isn't.
You're arguing that it's enforceable by saying fixed mags are required, but then you revert back to referencing the actual statute.... which allows detachable pre-ban magazines.
Healey's edict, which is not law, is the only time fixed mags are at issue (except for pistols).
That same edict, specifically gives Healey the right to declare some thing an assault weapon whenever and however she wants and she declares a copy cat weapon to include any of the following.
"The weapon has a receiver that includes or accepts key operating components that are interchangeable with those of a banned weapon. The relevant operating components may include, but are not limited to:
1) the trigger assembly;
2) the bolt carrier or bolt carrier group;
3) the charging handle;
4) the extractor or extractor assembly; or
5) the magazine port."
Would the fact that it's bolt action outweighs the above criteria? Maybe, but the bottom line is it isn't law. Entertaining it as such is just giving her power she doesn't have.
There is only ONE assault weapons ban. Bolt action rifles are excluded. ARs can have detachable pre-ban mags and one evil feature. That's it.
By even joking about "fixed mags" you're giving credence to something that doesn't deserve it.