In a lot of uh, fast food social media (Insta, Tiktok, Twitter) 'toxic positivity' is basically used anytime anyone commits a single offense of being too optimistic or endearing in a way that gives someone an instant knee jerk 'ick' or something, when they're in a bad mood and just wanted someone to also be as angry or depressed as them, in the moment.

...People who do not have narcissistic personality disorder understand that there's a bit more to it than that, namely long, established, continuous patterns in someone's behavior which indicate that this person has an enormous amount of privilege, does not realize this, to the point that they become blind to serious concerns and problems, and then those problems become worse and worse because of the toxicly positive person's nonsensical advice being detrimental and time wasting, or just vapid meaningless platitudes.

And then also, the privileged person often become overwhelmed when anyone lays out the basic facts of their reality compared to the privileged person, and then also they usually then get angry with the less privileged person for pointing this out, and now its your fault that you made me feel bad.

This can also happen at a large scale, where an entire organization or group acts like this.