There are no "one size fits it all". Some good games can be built by one person given there are right tools available and your skillset is align well. Problem with solo development is that you can't make a job out of it unless you are already have big community of followers or released something popular.

I sure it's possible to get $100,000 of budget for a new game as team of 5 people to release it within 6-12 moinths. Even without much of track record it's doable if you have cool prototype. But I pretty certain no one will ever give money to yet unknown solo developer to release the same game in 2-3 years.

Yet modern tools become better and better every year and even for $100-500 you can buy enough of assets to build something that look good enough in 3D. There are just certain genres and art styles that just require larger team.