I would say that it very much depends on the culture and use-case of the community.
If people @ me here it drives me nuts, but I recognise that I’m an outlier because of my profile and the fact that I spend my life on here.
In our internal Discourse instance we @ people if we need their specific attention but we actively don’t if we are just referring to them because it creates notification fatigue.
If I put on my community manager hat I would say that you should generally only @ someone if you are calling them into a discussion that they haven’t already been a part of.