As someone who has worked as an EM and an IC, I will say this. The only time the line between the two roles is blurred is when companies purposely blur it. Basically an EM role where the pressure is to get "hands on" and code. I always point out that what they are describing is closer to a Tech Lead, not an Engineering Manager.

Outside of those things there's no blur. The article is wrong it's not getting this way because of AI or because of remote work. It's this way because companies are purposefully misunderstanding the EM role.