This is a huge question and I doubt any SE answer could address this fully, but I would like to elaborate on a few points.
Effects of the Alaska Permanent Fund Dividend
I would argue that the primary success of the Alaska Permanent Fund Dividend is its positive effect on decreasing poverty. The effect on employment seems to be more neutral. Here is an exerpt from the latest research paper by the National Bureau of Economic Research related to the subject,
The employment to population ratio in Alaska after the introduction of
the dividend is similar to that of synthetic control states. On the
other hand, the share of people employed part-time in the overall
population increases by 1.8 percentage points after the introduction
of the dividend and relative to the synthetic controls. The
unconditional cash transfer thus has no significant effect on
employment, yet increases part-time work.
Given prior findings on the magnitude of the income effect, it is
somewhat surprising for an unconditional cash transfer not to decrease
employment. General equilibrium effects could explain why we do not
find a negative effect on employment. Indeed, in our unique setting,
the whole population in the state receives the dividend. Therefore, it
is plausible that the dividend increases labor demand through its
effects on consumption. And indeed, we find that the non-tradable
sector shows more favorable effects than the tradable sector. In the
tradable sector, employment decreases and part-time work increases,
while in the non-tradable sector the effects on both employment and
part-time work are close to zero and insignificant. Overall, the
evidence is consistent with positive macro effects offsetting any
negative micro effects, and leading to an overall null effect of an
unconditional cash transfer on aggregate employment in the long-run.
In my opinion, that employment didn't decrease is surprising and positive. But I have heard some people spin its effect on jobs negatively by mentioning how it didn't increase employment. My guess is as time goes on people will spin this data in whatever way they see fit.
On the 4th industrial revolution
Yang asserts that millions of manufacturing jobs have disappeared in the Midwest and that is how Donald Trump got elected. As the following chart shows manufacturing jobs have declined in number since 2000 without much recovery,
But stagnant wages have been an issue since 1970, and I think this has caused some push back among many economists that argue the effects of automation have been over-amplified over the effects of de-unionization. That said UBI could act as an expensive large scale form of unionization.
On the framing of payments
I hear a lot of people talk about how the government would "pay for something" and personally I don't like the framing of this question. It often weakly implies that the government can't run a budget deficit. In the Fifteen Fatal Fallacies of Financial Fundamentalism, William Vickery eloquently addresses this as follows:
Deficits are considered to represent sinful profligate spending at the
expense of future generations who will be left with a smaller
endowment of invested capital. This fallacy seems to stem from a false
analogy to borrowing by individuals.
Current reality is almost the exact opposite. Deficits add to the net
disposable income of individuals, to the extent that government
disbursements that constitute income to recipients exceed that
abstracted from disposable income in taxes, fees, and other charges.
This added purchasing power, when spent, provides markets for private
production, inducing producers to invest in additional plant capacity,
which will form part of the real heritage left to the future. This is
in addition to whatever public investment takes place in
infrastructure, education, research, and the like. Larger deficits,
sufficient to recycle savings out of a growing gross domestic product
(GDP) in excess of what can be recycled by profit-seeking private
investment, are not an economic sin but an economic necessity.
Deficits in excess of a gap growing as a result of the maximum
feasible growth in real output might indeed cause problems, but we are
nowhere near that level.
Note that while the above was written in 1996, the last sentence still applies in the year 2019. Notably, inflation is still below the 2% target. Instead we should always be asking does this expenditure make sense? "Make sense" is of course a broad term but vaguely we are concerned with whether it would increase GDP, increase life expectancy, decrease child mortality, etc. Or to put it differently, is this the best way to spend trillions of dollars?
On the effects of UBI
Bad environment? Lower class people will buy more drugs, alcohol, and stuff like that, creating a negative atmosphere or a bad stereotype in America
I think this is an unjustified fear. None of the UBI pilots so far have seen increased drug rate use in participants.
But the positive side is that America's economy can now renew itself since people are buying more goods
UBI implemented through a VAT tax and debt monetization is effectively a redistribution mechanism from those who consume more and those who hold more cash. Broadly, poor people should get more money to consume, which should boost GDP:
The IMF report said the way income is distributed matters for growth. "If the income share of the top 20% increases, then GDP growth actually
declines over the medium term, suggesting that the benefits do not
trickle down. In contrast, an increase in the income share of the
bottom 20% is associated with higher GDP growth."