I found this post on ARM MTE which was helpful in understanding the concept: https://www.anandtech.com/show/16759/sponsored-post-keep-you...

Seems to me this will have an execution overhead though, and that the best way to improve security would be to finally move beyond C. Most modern languages make buffer overflows impossible.

Except all those fine people writing UNIX clones and embedded stuff will never do it, so here we are.

It was already known since the early days how bad C was versus the competition.

UNIX made it famous, UNIX won the server room wars, UNIX will keep it going.