You replied to the wrong guy, but I think they rather meant it as “unless you’re using a password manager (…because password managers are generally capable of storing extra data)”. 😅

I mean, even if it can’t store extra data in one entry, you could still create multiple entries for a single account and just name the entries similarly.

And to give an example of a password manager intentionally kept so simple that, well, there is a solution, but it is somewhat choose-your-own-adventure: https://www.passwordstore.org/#organization
(You can get GUIs for it, which may have a premade solution after all, for example: https://f-droid.org/packages/app.passwordstore.agrahn )