This didn't just start now, for a long time investors and traders have used tweets and actions of people who have some kind of influence on the market to make their short term predictions. The thing is, this is usually a short term strategy and as time goes on, those people no longer have as much influence as they did, for example, Elon Musk. Thus traders still use technical and fundamental analysis, particularly when you are looking at the long term.
Yes, this could have started before but the thing is, the influence before is not that extreme, unlike today even Trump’s date of inauguration is expected to have a price surge in the market. However, I know this kind of strategy may not last forever. Fundamental and technical analysis are still the most basic and reliable ways when trading, it’s just that today, they‘re quite underrated.