It is a bad idea to listen to advice from strangers, and if that advice is about investing, you should probably take advice from people you know very carefully too.
It's not about whether you know this person, but whether he has the right qualifications to give advice on investing. If a person has a successful investment experience that he can demonstrate, then why not listen to his recommendations. It's not about mindlessly following his advice, but about listening to them and acting on your own interests.
As for investing in new projects, there are a lot of them now, so it is better to invest in time-tested ones. Investing in new projects is very risky, given that all cryptocurrency is risky.
Investing in time-tested projects can also be questionable. Most of them don't undergo any cardinal changes and the price "marks place" for years. Why buy something that doesn't make a profit?
In the case of new projects, the risks are extremely unjustified. Only the lazy one has not issued its own cryptocurrency and there are a lot of such projects. Most of them are "stillborn" and investing in them will result in a loss of investment. The probability of guessing a successful project is the same as winning in a casino. Maybe it's better to play in a casino instead? There, at least you get a win right away and you don’t have to wait until interest in your project increases, increasing the value of their coins.