My first thought is that it’s there because there is no range hood.

That WAS for a range hood or micro hood.

If so, it would seem that the update was to make thermal sealing take precedence over removal of kitchen cooking fumes. If there is no opening in the kitchen for this vent, sealing it on the outside might have little benefit depending on how it is sealed or blocked on the inside. One might want to be sure it isn't some heater exhaust vent brought up the interior wall; maybe check it intermittently for exhaust.

@kaseki what is thermal sealing?

I see a remarkable number of responses on this topic from web searching on "thermally tight house." You may wish to do this to gain insight.

Briefly, in order to minimize heat loss and "save" energy, various means of insulating houses have been developed. Included in this scope are means of sealing against air leaks. But without fresh air, one lives in a chemical 'soup' from cooking fumes and out-gassing of materials such as plywood adhesive and furniture stuffing.

To get fresh air into the house without loosing too much heat, heat recovery systems attempt to transfer heat from exiting air to incoming air. For thermodynamic reasons, this can only be partially successful. With a sufficient hood exhaust flow rate for removal of cooking effluent, replacement air is required, and heat recovery is not, to my knowledge, performed on exhausted greasy cooking effluent. Hence, during cooking with adequate ventilation, one does not have a thermally tight house.

In my view, a higher heating bill beats a higher health cost bill. However, the energy costs in treating illnesses induced by poor ventilation do not seem to appear in arguments for saving energy by sealing houses.

On this site, there may be more on heat recovery in the HVAC forum, or search out "indoor air quality -- IAQ" comments in this forum by @opaone.

I would go to the local building dept and ask to see all documents for your address. You should already have the condo deed drawiings.