[Discussion] Changing PASSWORD_DEFAULT to Argon2

Hi all, I'd like to gather opinions on the possibility of switching PASSWORD_DEFAULT from bcrypt to Argon2id. A few reasons to do so: - bcrypt has a limit of (and silently truncates at) 72 bytes, which may seem like an acceptable thing at first glance, but does cause many headaches - Argon2 is superior in every way and widely recognized as the gold standard today; I've even encountered people who mistakenly believed it is already PHP's default - While both algorithms are (by today's understanding) considered safe from quantum threat, Argon2's memory hardness makes it future-proof by design But there is one contentious circumstance - bcrypt is entirely bundled with PHP, while Argon2 has external dependencies: libargon2, libsodium, or (since PHP 8.4) openssl. The addition of OpenSSL is key, because it's the most ubiquitous and a practical must for almost any environment, IMO making changing PASSWORD_DEFAULT viable. But am I right to think that, or is any external dependency likely to kill the proposal? That's what I want to gauge before fleshing out an RFC with the greater detail it deserves. Cheers, Andrey.