This isn't true if your objective is just to protect wealth long-term.
I said illegality constrains the usefulness of cryptocurrency. Long-term gains is one of the remaining hypothetical uses but other uses are limited. So your claim doesn't refute my point. With fewer practical uses, we might see bitcoin's long terms value decline but that's speculation.
Wealth storage is a practical use case. This is a weird thing to grasp, but it's actually perfectly reasonable (I.e. utilitarian and stable) for an asset to be "purely monetized", in the sense that it has no value whatsoever except from its capacity to store value.
That said, you're right that ability to actually spend bitcoin probably shows up in any PDE that accurately models its market dynamics. If 90% of countries on earth ban bitcoin, and those bans are well-enforced, bitcoin probably won't be very valuable.
It's one practical use case. Bitcoin's value rests on multiple use cases and eliminating other uses cases reduces demand for bitcoin. And that effect also reduces bitcoin use for wealth storage (but might not eliminate, sure).
I said illegality constrains the usefulness of cryptocurrency. Long-term gains is one of the remaining hypothetical uses but other uses are limited. So your claim doesn't refute my point. With fewer practical uses, we might see bitcoin's long terms value decline but that's speculation.