No one can tell this Rivian IPO is a good stock to buy. Because no one knows What exactly the things are. If you have enough resources like money, knowledge of the stock market, understanding, etc. then you can enter the stock market.
Without having knowledge if you enter in the stock market, there is a high probability that you will lose your money. Stock market is a game. If you have interest in the stock market and you stay updated every time then surely you have seen a big increase or decrease in stock price. No one knows when the stock will go up or down.
Experts only predict the future for the share price but they do not guarantee anything. They only said this as per the current growth of the share price.