Friends backed out of the trip, how hard is solo traveling (emotionally) ?

Mfs backed out one by one, I'm the only one going now. I'm not scared of being alone but being part of a group would have made everything easier.

I'm not a influencer or youtuber who will document alot and keep myself engaged that way. I will just be awkwardly going from one destination to another, standing in metros, waiting in queues, eating alone at restaurants, rarely speaking to people apart from hotel/konbini staff or the usual small talk with locals/other travelers. I don't know how mentally stimulating all of this will be. Will I be enjoying or start looking for moments of connection like in the movie Lost in Translation.

People who have solo travelled Japan, what was your experience like?