It’s not an assumption. I’ve investigated it and asked about it. Aliases cannot be transferred from one Proton account to another. If I upgraded to Proton Unlimited, which I have no desire to, and cannot afford, I would not be able to automatically transfer all my aliases from my Proton Pass account. The rest of my Proton data can be transferred, but not my aliases.
I’m still waiting for an explanation of how exactly I am BSing.
I do think the utility is limited if your contacts are not established in the privacy/proton ecosystem, regardless there are plenty of other recovery methods.
Thank you.