Are Slovaks foreigners too?

Technically speaking, Slovaks living and working in the CR are foreigners, unless they hold a Czech passport, but are they really foreigners? They speak a similar language (and often master Czech as well) and have similar life experiences. To lump them in with people from, say, Mongolia or Mexico who came here without understanding a word of Czech is fatuous for any reason other than pure statistics. It's useful to know that foreigners make up 4.15% of the Czech population, but it's much more indicative to know that without the Slovaks, foreigners make up 3.38%. A recent Deloitte study found that foreigners account for about 25% of the board members in the Czech Top 100 companies, but the study didn't break out the number of Slovaks. In the top 10 companies, we counted two Slovaks, or 5.4% of the total, not including Andrej Babiš and three other Slovaks with Czech passports. Slovaks make up a far greater percentage of top management than of the overall population of foreigners. Because, after all, Slovaks aren't really foreigners, are they?