Because according to him Bitcoin is a small number of people who have a lot of Bitcoin. They can easily go down on the bitcoin market if they want to.
Example: Cz. Craig wright & Michel Sailor etc.
Looking forward to the well thought out opinion of the experienced in this regard.
Sounds like he doesn't really know much about Bitcoin. Any financial asset that acts like an investment is going to have a small number of people holding a lot of it, because a small number of people hold a lot of the wealth of the world.
And, so you are implying your friend is rich? Usually rich people are smart enough to want increase their wealth, and Bitcoin is pretty much the best way in the world to do that these days, so I'd say your friend really doesn't understand the finances whether he is rich or not.