"Why do you think so many people oppose a UBI even when nearly everyone can acknowledge that our current social safety net is deeply flawed?" - @stonemasoner
In my opinion, part of the reason that many oppose UBI is that they are concerned that a UBI system would be added on top of our current system. This would have disastrous economic consequences and be completely unsustainable. While Dr. Trost's lecture on Universal Basic Dividends had many great points and is definitely better than our current system, it seems like reaching its goals unscathed would be near impossible. In addition, this would drastically reduce the power of the federal government which would be fought by the powers on both sides of the political isle to maintain their authority. Overall, many oppose UBI because it is unlikely that an ideal form of UBI would actually be put into place.
Secondly, a large portion of the people views UBI as a handout by the government which many are opposed to. They may view it as rewarding laziness or unproductivity. In addition, many in the US have a mentality that they can do stuff on their own and may even find "free" money insulting. This largely comes from a lack of understanding of how UBI would actually work and low views of our current social safety net. In general, opposition to UBI may actually come from the failure of the US social safety net instead of providing a reason to support the concept.
In general, the best way to educate people on a concept like this is to share meaningful information about it. Universal Basic Income sounds like a very socialist concept at first glance, so it is important to make the distinction and help others realize what it has to offer, In addition, it is also critical to educate others on the non-negotiable aspects of the system such as it is a constitutional amendment, has a flat tax, gets rid of all other safety net systems, and is only available to US citizens. Overall, a Universal Basic Dividend has the potential to reshape America for the better by maximizing mobility and freedom, but it needs to be done correctly and many have a valid fear that UBI will be another tool to increase the power of the federal government.