Are you sure you did not forget to select the query parameters as values for server connect sort and direction parameters?
In App Structure select your Server Connect component, the you will see its parameters in the properties panel. Bind the query parameters there.
Because you have used sorting please just check out the bindings to make sure you use the .defaul('') data formatter. Productivity Tips & Tricks look at tip 1 as I do not think this was an issue at the time of Brian creating that tutorial video.
It is not needed to use this.
It may cause sorting issues if some of your database table columns is returning null values. That’s why Paul suggest adding this to such columns.