To answer your question I would have to step into ideological territory. IMO, these things count as signs of adulthood: Having a stable relationship, building

To answer your question I would have to step into ideological territory. IMO, these things count as signs of adulthood: Having a stable relationship, building a family, building a business or being engaged in your community somehow. In essence giving and contributing, instead of (only) taking and benefiting from society. Kids are allowed that, adults have to be pillars of society. I know this sounds conservative, but it isn’t. Its just the only way a society can work and persist. The OP argued that we should make adulthood more attractive. I agree. Depending on where you live, life as an adult can be worthwile. I find that the key ingredient is community and social bonds.