Adding in tag barrier:height-restrictor as per your report of a yellow bar. https://www.openstreetmap.org/changeset/155984893

Generally speaking, a lack of signage means that the legal max height is within the default max height of general traffic in the region (in SK, that's 4.15m according to SGI). But given that this is the entrance to a parking garage, that likely is not a solid assumption to make. If you remember how tall this entrance looked and it did not look like it was 4+ meters tall, we can use the "below_default" value here.