How is UBI a shared good? It definitionally takes from some to give to others. That is the opposite of a shared good.
Taxes are theft when taxes are used for nonpublic goods. That means any good that is not both nonrivalous and nonexcludable. We tend to allow the bluring of nonpublic goods the more hyperlocal we get, since we can more accurately address needs. But such nonpublic goods are still funded via theft.
What's wrong with paying for that which you use? It's a consumption based model, and I do believe it would lead to better economic and societal outcomes.
No one else here seems to share this axiom. I appreciate that it’s important to your worldview but it’s also why you and everyone else are arguing past each other.
The only way to guarantee competition is to punish predatory practices of large companies against small ones, which means, surprise, regulation.
Any history pre-new deal shows how incorrect this standing is.
Also, taxes aren’t theft. It’s the cost of living in society and providing for societal, shared goods. “Streets are theft!! All roads should be toll roads!” Want a grand society…