That's not true. In a pyramidal scheme, the profits of old users are directly generated by the incoming money of new investors. it doesn't necessary mean new investors lose; it means that after some point, the whole thing will collapse, and then they will.
From that perspective, every stock in the stock market is a pyramid scheme because the price is rising only because the people are buying and selling it.
Hence the early investors are gaining profits just because the new investors are buying it at higher prices.
If you argue that companies have intrinsic value and so the prices are rising then bitcoin's intrinsic value is the trust of people over it and that's why the demand is there for it and the price is rising.
So are stocks from a pyramid scheme too? If yes, then bitcoin is too.