The founder/boss has a closed mind and is not willing to learn from his employees.
His mentality is just to hire people to work from him, instead of with him. Also, the company does not offer real accessibility of career, there is none willingness of shared ownership, zero onboarding making feel you unwelcomed and some of the senior developers are talentless and arrogant. This is also a reflection of the boss managing style since he does not bother to take part in team bonding whatsoever.
If you are a junior, stay away: you'll be moulded with incredible incompetence and a toxic environment.
If you are mid or senior, Tokyo has really way much more to offer you. Diverta is not the place you'll ever need in your life.