That is interesting; I didn't know European countries would prefer sugar over corn syrup. Do people there also have the opinion that real sugar is more subjectively superior in it's taste and aftertaste?
I don't know that anyone has an opinion on it, regular sugar is just the norm. Corn syrup is just not common enough that people would be exposed to the point of single it out. We don't really have a « big corn » lobby, and GMOs which are meant for that type of production are verboten anyway.
The quotas on isoglucose have been lifted a few years ago in the EU, so that might become more common. But I think it's really meant for export, especially considering sugar is meant lower in manufactured products anyway.