TBF the Giro has never really balanced out climbs the same, and the Tour has started getting extremely creative with their categorisations recently. Vars HC? Côte des Chevrères cat.1? I mean FFS.
However, because normally the Giro only gives out its highest mountains points for the Cima Coppi and has historically had no HC status, things like the Zoncolan, Mortirolo, Monte Grappa, Monte Bondone, Manghen, Sampeyre and others which are clear HC-level climbs but not at sufficient altitude to ever be the Cima Coppi are simply given cat.1 status; this often means that either the race is very stingy with cat.2 status for some seriously tough climbs (San Pellegrino, Valparola, Falzarego, Tonale, Cibiana and so on have seen it in the past), or that climbs earlier in the race given cat.1 status like Rionero Sannitico or Monte Carpegna are ridiculously categorised with the same points available as a climb like Grappa or Mortirolo (like in 2008, for example).
Finestre in 2005 is the only example that comes to my mind of the Giro actually implementing a "HC" category:
This was as the Cima Coppi that year was Stelvio. In 2011, it was reduced back down to cat. 1:
Since then, when included, Finestre has been the Cima Coppi, which has meant that it at least gets that 'special' mountains points value.
Based on the old Giro GPM, cat.3 was 3-2-1, cat.2 was 5-3-1, cat.1 was 10-6-4-2-1, an MTF (of any category considered worth giving points) was 15-10-6-4-2 and the Cima Coppi was 20-15-10-6-4-2.
I can't remember exactly what points were given for Finestre back in 2005, but it was a special category of its own.