The important part is that the NIST password advice is meant to be read as a whole. Often I see people quote snippets out of the advice, but unless you read and understand the whole document, you run the risk of reducing your security posture.
While that's technically true, the advice is meant to be taken in the context of the rest of the advice (e.g. longer passwords, checking against compromised passwords, etc...).
If all you did was to change all your passwords to never expire, you'd be reducing security.
Not necessarily. Except in cases of gross negligence, such as storing passwords in plain text, the human is always the weak point in a security system. If you make people less likely to leave their passwords on sticky notes, perhaps by removing password rotation, then you have improved the weakest link of the system, and improved the security of the system as a whole.
A portion of our customers will ask us about NIST, but it's slimmer than I would have expected.