I was able to tackle that road with a gravel bike (47 mm tires). The weight of the bicycle and the extra luggage was about 22kg. On the way up I had to push the bike around 5 times because the rocks were too big (never more than 2 minutes). It definitely demands a good level of fitness and agility to get over it but is definitely doable. I surely recommend a hardtail bike but a gravel can do the job if you're brave enough. Landscapes were so beautiful it is worth it! The descent was quite steep and sometimes technical aswell.