Hello Ana,
If we want to say something to a specific person (after any comment from him), We need to type his name there explicitly, Sometimes difficult or maybe a spelling mistakes.
So that, It will say that I'm pointing to someone by mentioning his name.
For example, @Ana, As you said...., @Amol, Can you give some detail....
Unlike in other community, We use @<name> to specify someone from the friend list, So that the person will get a notification that someone has mentioned you in a comment, etc.
For better clarity and performance, maybe, You can show a list of only those people who have commented on that post.
And also you can put a link to that person's profile in that tag to check it easily.