> UBI isn't meant to be a full replacement for an individual's economic activity.

Indeed not.

> It is /basic/, which is to say, it will cover the basic necessities.

Honestly, I think this is one of the fundamental mistakes UBI proponents make: proposing the idea that there is some particular level that UBI should reach.

UBI is much more coherent of an idea if the "basic" is recast as representing simply a baseline, rather than targeting basic necessities, which are, critically, not a fixed target anyhow, but a moving baseline determined by social expectations, which UBI itself will affect.

> The whole article is based on the assumption that once basic necessities are covered, huge numbers of people are going to call it a day and cease economically profitable activity.

Which is pretty silly for a number of reasons. Mostly, ignores a lot of basic observations of human behavior and the difference between UBI and the systems it displaces:

(1) People strive for more material wealth, so long as that provides perceived marginal utility (there's some evidence that beyond certain very high incomes -- IIRC, studies ~10-20 years ago had this in the neigborhood of $200K/yr in then-current dollars in the US -- but even so people strive for more when they have that much because of perceived utility.)

(2) People's expectations and self-perceived "basic needs" are strongly influenced by comparison to others visible in their society, not merely absolute conditions; UBI improves the absolute condition of those without capital or labor income, but it doesn't remove the incentive to strive for more (in fact, compared to a system with a means-tested safety net, it increases it.)

(3) Capital income is still a thing with UBI: this is perhaps them most significant oversight in UBI criticism. Its true that UBI is often posed as a protection against a world in which an ever increasing share of the population is unable to find work with significant value, reducing (at least, in a relative sense) the income of workers, it is not intended for a situation where there is no opportunity to strive for more. Between UBI and what people can make from work, there are opportunities to acquire capital, which is the route to development which remains open even if labor opportunities become scarce.

(4) But labor opportunities won't disappear in the near term, though many may pay less per hour (especially at the entry level.) But UBI makes lower-pay labor both viable (by providing support which isn't removed with additional labor income) and legal (as it is usually posed as replacing minimum wage -- I personally prefer a phase-out where minimum wage is reduced as UBI ramps up), which increases rather than decreasing work opportunities.

> We're not going to turn into a banana republic where only the economically elite and the political class keep each other happy and everyone else are kept just happy enough to avoid revolution.

Well, UBI won't drive that, at any rate, and largely opposes it. There's a very good argument that the first part is largely true, and you could argue that the one thing that's been happening in recent years is the fine tuning of just how little is necessary to hit just the point where the second half is true, too.