Yes I believe strongly that small investors can still make good amount of money from Bitcoin investment, the difference between rich investors and poor investors is the rich have the money to buy bigger amounts in their own DCA strategy, higher buying power.
The poor as smaller buying power but with DCA strategy it's still going to be effective, every $50 per week into Bitcoin will surely change your life in the future if you can keep up with the DCA for let's say 3years straight.
It's all about how long you can keep buying Bitcoin with what you can afford, without the money affecting your daily life in a negative way, I mean you are still able to live right, pay your bills and eat healthy,
The phrase "good profit" is relative. Investment is like the computer: garbage in, garbage out. That is the amount you put in would determine how much profit you would make. So if OP is expecting to make a fortune by investing $1000 in Bitcoin, it wouldn't be possible even if he keeps it for more than one cycle. Bitcoin is not a Ponzi or get-rich-quick scheme.
My advice to those who want to make more money investing in Bitcoin is to seek means to invest more money. Low-income earners can seek alternative sources of income to increase the amount they invest using DCA.