You’re mistaking matSortStart
for matSortDirection
.
Try this:
<table matSort (matSortChange)="sortData($event)" matSortActive="name" matSortDirection="asc" matSortDisableClear>
https://stackblitz.com/edit/angular-defaultsort?file=src/app/sort-overview-example.html
matSortStart
can be used to reverse the cycle used when sort (e.g. when the user clicks to sort, it starts at desc instead of asc).
Edit: Thanks Ben for providing an updated example