Friend thinks fractional shares of Bitcoin are not worth it

Earlier, my friend & I had a conversation about cryptocurrency. It's worth noting, neither of us know much about this topic. While I expressed interest in purchasing fractional shares of Bitcoin, my friend argued that fractional shares wouldn't really pay off because Bitcoin is already so expensive. Only those with money to spare could stock up on Bitcoin & reap huge profits from its eventual growth. I insisted that there's still a world to cryptocurrency that neither of us understand & that I don't think it's that simple. I skimmed a few articles & watched a few videos speculating on Bitcoin's worth in the years to come (some anticipating that it'll reach six figures & eventually millions in the next decade). I also stumbled upon a few Reddit posts encouraging the investment of fractional shares because Bitcoin is comprised of smaller units known as Satoshis. I don't fully understand this, (unless it's indicating that investing in Satoshis will eventually pay off as they'll be worth more than a dollar). I also understand that different cryptos serve different purposes. Concepts like blockchain technology, smart contracts & other topics far beyond my understanding are barely the tip of the iceberg when it comes to crypto & until I can better understand it, I prefer to keep an open mind towards it. Especially when nearly everyone more financially literate than myself praises Bitcoin & suggests that even the most infinitesimal of investment in it today can make us the "elite of the future." So in brief, I'd like to know your thoughts as to whether investing in fractional shares of Bitcoin (or Satoshi) is a good idea for the long haul & how much do you think Bitcoin will be worth in the years to come? Is it realistic that a fractional investment of like $150 in Bitcoin can see returns upwards of six-figures? Or a meager couple of hundreds?

I will continue educating myself on the topic. Feel free to refer me to any resources that will help.
Much appreciated!

EDIT: I'm going to make a drinking game out of everyone who continues poking their head in just to remind me that Bitcoin "shares" is incorrect terminology after it's already been acknowledged.