Fees are necessary, but there are basic requirements in trading, such as trading volumes. I cannot use a platform with zero fees and have no trading volumes, the execution of the order will settle for a long time and thus miss the opportunity to make gains.
Also, when your trading volume is low, you need to execute the orders using "market order
[1]," which is always expensive and you lose part of the profits if it does not achieve a loss.
Do not forget about security, support team response, KYC limitations, trading/login speed, all factored with fees that make the user use a particular platform.
Also, fees can be reduced if you have sufficient experience.
[1]
Types of Orders | Investor.gov