Not really, "they" has been used to refer to a singular gender neutral subject for way longer than you've been alive. Whether it refers to plural or singular subject, and often who it refers to, is all pulled from the context of the story.
PS Communication normally is about clarity. This type of intentionally confusing change in grammar is straight out of Bolshevik propaganda. Just like the phrase "politically correct" which literally means its wrong but I will have the state use violence against you if you point out that its wrong.
Just because you heard it 20 years ago, does not mean that it was not used before.
In addition, "it" is not used for people. Yes, it is a gender neutral pronoun, but would be considered very offensive if you refer to a person by "it". The only example where you can use it usually is a baby whose name and/or sex is not known, often prior to them being born.
The phrase "politically correct" mostly only used by "anti-woke" snowflakes who believe they are better than those who tell others to leave non-binary folks alone, yet at the same time will rage all day just because some said that they're a "they" or some silly little thing. As if they've got nothing else to do in life but get angry at someone for having a preferring on how they want to be referred to.
Also implying that the natural evolution of the English language is some form of propaganda is wild to me. The language is essentially an evolution of German, with heavy influence from Roman/French and Old Norse. Saying that it is propaganda is like saying there's been some psyops by millions of people happening over centuries to mislead millions of other people.
The only correct thing you've said is "communication normally is about clarity". Honestly, to me, it feels like that hasn't really worked on you. You're certainly not clear about the history of the English language.
[0] https://www.oed.com/discover/a-brief-history-of-singular-the...