Someone said that Bitcoin is for the rich, but that's not completely true. It might feel like Bitcoin is for the rich due to the media focuses on celebrities and billionaires buying and benefiting from Bitcoin. This creates a perception that Bitcoin is a rich person's asset. Even during network congestion, fees can spike making small transactions very expensive. But let's not forget that Bitcoin is neutral, it can empower the rich or help lift the poor, it actually depends on how communities adopt it. So understand that Bitcoin is for everyone, you can buy tiny fractions, not until you afford a whole Bitcoin.
Base on the context, I was expecting you were going to discuss about Bitcoin being for the rich in the aspect of its price, because currently only the rich will have been able to afford to purchase a whole of 1 BTC if we consider its current price @$120k and If it weren't divisible into fractions, it would have now turned into an asset class or investment opportunity only meant for the rich people.
Only (like you said) if bitcoin wasn't divisible and who ever is buying will have to buy in whole numbers like 1,2,3,4 and so on, but thank goodness that Satoshi and those who assisted in the development of bitcoin thought this out really well before developing the coin, knowing fully well that only the rich can afford to buy when the coin have become very expensive in price.
Anybody can buy any number of bitcoins, and those who can not afford the money to buy one full bitcoin can give attention to buying Satoshis, many have through buying and keeping/saving of bitcoin Satoshi's made alot of money for their selves.