Maybe the developers even know better, but were forced to do it by project managers (or other management)? Because this sounds like just the kind of "security issue" a manager could get hung up on...
Not everyone's boss is even a little bit reasonable. You might be both a very skilled engineer and capable of explaining things very clearly and persuasively, but communication always takes two (or more) parties, and both those parties have to be approaching that communication in good faith in order for the actual skills of communication to really matter.
Most people are reasonable, including people who happen to be managers. Most people will listen to you if you make informed, persuasive arguments. And even when they don't, most people will be able to articulate to you a perfectly valid reason why the thing you want to do can't happen, or can't happen yet.
I'm not normally a fan of ecosystem lock-in, but using Google products as my password manager, browser, and mobile OS means I very rarely have to use my clipboard for passwords, which is a good feeling. Unlike a third-party password manager with a great browser extension could offer, this ensures seamless autofill with most mobile apps nowadays, too.
Some managers are unreasonable, and will not change their minds about what they've decided because of the arguments, no matter how rational and well-expressed, of people beneath them.
Declaring categorically that any engineer who cannot persuade their manager not to do something bloody stupid is a bad engineer is insulting to engineers who are, in fact, in exactly that situation, and is, from where I sit, part of a very large category of mistake where someone tries to avoid having to apply human judgement and critical thinking by making a hard and fast rule about things that are much more nuanced and fuzzy.