This is a great rundown of the economics of the independent solo advisor business model. While this is focused on RIAs, I see the same thing anecdotally in the independent b/d rep/hybrid space.
There are many tools, resources, platforms, and business models that allow a solo advisor to take care of his or her clients very well and make a great living. Kitces' article is detailed and in depth (as always), but worth the read if you have any doubt in the financial viability of setting up your own practice.
Teams have great advantages and are wonderful for many people. However, that doesn't mean the "Lone Ranger" type can't continue to thrive.