Has Vaultwarden said anything yet? I imagine that, if necessary, given that bitwarden's client is still open, at the point they choose to try and close it, we, the users, can fork it and establish it for vaultwarden, correct? Or, maybe even the vaultwarden team will think about forking it themselves and making a light client as well to pair with the current server.
But Vaultwarden can exist without "leeching" they just haven't needed to yet. That's more symbiotic than parasitic. The parasite class just took over Bitwarden after all.