Why Is MIT License So Popular?
MIT license is probably the most famous open source license ever. All types of software can use it and since it's also one of the most used it's easily recognizable by others. Like mentioned in the other responses it's also very popular among commercial software which gives it even more credit.
With the MIT license you do not need to provide the source code when distributing but you must provide attribution (ie credits) to the authors of the MIT licenced code you've used. In both cases, you're entirely free to sell the software for anything you like.
Can you take an open source software, modify it and sell it if the license is ...
Their interpretation depends on the technical usage of the licensed software. Therefore, it's difficult to determine the legal risks of using open source software, especially for developers, who are not usually legal experts....Top open source licenses by risk.
Top open source licenses and legal risk for developers - Synopsys
From all available FOSS licenses, the MIT license remains the most popular. In 2019, researchers found that 27% of all open-source licenses on Github were using the MIT license because it is short, to the point, and optimized for developers.
What is the MIT License? Top 10 questions answered | Snyk
Many of the issues with the license are due to the evilness of software patents. ... Because the MIT licence has no explicit grant of patent rights as a condition of use of the code you open yourself up to abuse from bad actors.
The MIT licence is community hostile - Janis Lesinskis' Blog