The Skopje 2014 project is, in a way, an attempt at forging a national identity that's equal parts Slavic and neo-Ancient-Macedonian -- and the Albainans, feeling left out, have protested quite loudly about it. More on that here: https://www.degruyter.com/document/doi/10.1515/soeu-2018-003...
Also on the Wiki page:
> https://en.wikipedia.org/wiki/Skopje_2014
> "Sam Vaknin, a former adviser to Nikola Gruevski, has stated that the project is not anti-Greek or anti-Bulgarian, but anti-Albanian. In an interview, he said "Antiquisation has a double goal, which is to marginalise the Albanians and create an identity that will not allow Albanians to become Macedonians.""
All very interesting, I think. It's a nation that's trying to find itself, trying to build up a coherent national identity in real time.
As for the Greek thing, it's totally obvious that Ancient Macedonia is within the borders of modern Greece. Philip's palace at Aigai is a ~4 hour drive from Skopje, and indeed south of Thessaloniki. So the N.Macedonian position re: Alexander the Great is a little bit farcical. But I suppose they could say that they are inheritors, of sorts, to the Roman Province of Macedonia...