The term Baltic originally included Finland in-between the World Wars after the 4 countries gained independence from Russian Empire under similar circumstances. At the end of WW2 as Estonia, Latvia and Lithuania were occupied by the USSR, Finland was left as the odd one out and started to move towards the Nordics.
The terms Balts and Baltic people are actually very specific and refer to just Latvians and Lithuanians. Now that the 3 countries are independent again Estonia is left as the odd one out because calling Estonia Baltic is accurate only in a geographical sense, not ethnically or linguistically. Estonians and Finns are Finnic people and speak Finnic languages. Finnic people are Uralic, same as Saamis and their language does not belong to the Indo-European language family. This means Swedish and Latvian are more connected to Punjabi than to Estonian and Finnish.
Furthermore, the original use of the word Balt appears in the 19th century referring only to the Germans living in the region.
Given the potential confusion that can come from this mix usage of inaccurate terminology, we propose that the term Baltic should be used to refer either A) just Latvians and Lithuanians (like it is for ethnic and linguistic references), or B) all the countries around the Baltic sea (as it should be geographically).
So if Estonia is not really Baltic, question arises: what is it? And if Finns and Saamis are both considered culturally Nordic, why aren’t Estonians?