The right thing to do is to bring the issue up with whoever is running the website. If they decide not to act on it because they think they know security/UX better than Google/you, they're stuck with crappier security/UX and the market should sort it out.
I've actually managed to convince a company to stop prohibiting copy-paste on logins by pointing them at the new NIST password guidelines. I don't expect this to work for every company, but if they intentionally don't change, it's okay to name and shame them for it. Whether it's a UX sin or security voodoo.