Nobody denies that there are areas in Finland with a majority of Swedish speakers or that Swedish was the official language in Finland during the Swedish and even the Russian period of their history. But the overwhelming majority of the population spoke Finnish as documented by the repeated requests of the representatives of the farmers in the riksdagen to provide Finnish translations and to consider Finnish speakers for the appointment to various official positions - both requests remaining unfulfilled.
The Finns and the Swedish minority in Finland have struggled with this issue for a long time but have finally reached a compromise they can both live with, my wife's family being an example that many considered being from Finland above these cultural issues. She is the product of a marriage in the US between a Finland Swedish and a Finnish family.
What this issue boils down to is a determination of what population group an individual belonged to with respect to what Preferred Name or Current Last Name to use. For sure, the name on the original record should go in the LNAB field but for many Finns the Swedish record is akin to a Latin record everywhere else in Europe, it is not the name they used in daily life.