There is another point to consider: If you are developing an application of some sort that is going to include a database, and you plan on selling it. ..then MySQL has some licensing issues you should explore before using it.
I know a guy who was developing a book-tracking database. He called Oracle and was trying to get some definitive answers to what licensing fees would be like if he included a MySQL database in the project, and then sold it.
He never got a straight answer. One person said one thing, and another person other things.
Finally, he just used Postgresql so he would not have to worry about it. This was before MariaDB was stable.
Like the other guy said: there is no reason not to run MariaDB, but especially if you plan on selling your application.