This is a brilliantly concise explanation of this. I think it slightly glosses over one thing, which is that in any case where it might actually be implemented, UBI is basically a trojan horse to undercut and defund actually existing and useful welfare programs. That is what happened in Finland: https://www.socialistalternative.org/2017/03/07/finlands-bas...
The rhetoric in that linked article sounds like a fetishization of work, the old-school Communist praise of the labourer as the ideal human being. That is, the authors call for creating more jobs and building factories. That is a turnoff to those socialist-minded people who feel that work sucks, it is something our modern society ought to be avoiding by increasing automation.
SA is completely in favor of automation and actually calls for reducing the workweek. But under capitalism, automation is used to drive down wages and increase the ranks of the unemployed, which is the primary concern of the (growing amount of) people who are living paycheck to paycheck or unemployed.
