I think the real problem is not so much Jeremy Crawford's answer, but rather the use of the word "willing" in the cantrip itself. How is a "sheathe of booming energy" supposed to know if you are charmed or otherwise compelled? Is it actually an elemental spirit with an absurdly high Insight skill?
For my home campaign, it will simply not trigger on forced movement (you get pulled/pushed past the barrier before it has a chance to trigger), but if you move under your own power (i.e. spend your movement), then it triggers. Even if you are feared, charmed, or otherwise compelled - just like an Attack of Opportunity.