> Is it fair to say that AI and ML are synonymous now in 2023? Or are there people who are still actively working on non-ML techniques for building AI?

AI means "I am a lay person or a media person talking to lay people".

ML means "I know what I'm talking about".

AGI means "I know what I'm talking about but I don't know what it is or how to build it".

The term 'AI' followed a previous hype-then-disappointment curve and got a bad name. Researchers restricted themselves to "things that worked" and called it Machine Learning to imply that we are teaching models and they are learning which is obviously true, rather than implying "this thing is intelligent" which it probably isn't.

Side topic: humans keep moving the bar on what counts as intelligent. It used to be "can play chess" and it then was "can play Go and hold a conversation" and then it was "can draw and show creativity". Humans will keep moving the bar on the definition of intelligence for as long as (humanly) possible.